Probably the AI just got stuck after so long. haha
Or maybe... this is true and... Quake bots developed themselves and created in their own strings, intelligence.
So someone crashed/closed the server so they wouldn't become the next SkyNET.

In RTSes, it's really hard to pull off a good human-like AI. Most of them either overpower AIs by endowing them with godlike micromanagement capabilities, and you get to feel like you're fighting against a person with 6 sets of hands, or give them unfair advantages like the ability to see the game map at all times, get a constant stream of resources or spew out units at an alarming pace.

I don't think we're there yet. I've yet to come across an AI that feints, lays traps or outright uses any deception tactics to gain the upper hand. The usual AI will just send a variety of hordes down your path and expand indefinitely or, at most, will sometimes try to open a new front should it fail repeatedly in its attacks. As far as realistically simulating battlefield situations and morale, I think you are right - the unit AI in the Close Combat series is very well done.

Wouldn't be incredible to play a game like Mount & Blade agaisn't advanced AI?
Can you imagine an advanced AI giving orders in real time for troops to counter, make ambushes, advanced formations switch... man.

I give you guys a recomendation for 4X games: Oriental Empires.
Can't say Oriental Empires AI is that good, but I enjoyed playing with it's battle system. Completely different from Total War, almost turn-based.

I'm suddenly reminded of playing Chronicles of Riddick, escape from Butcher bay. I realized while sneaking that the 'Smart AI' was little more than pre-scripted activities when you passed certain barriers. Otherwise they are more or less 'chase and shoot' AI.

Still, making a general AI to make certain activities/plans wouldn't be too hard, or to program logic into the map so it feels more like playing against a human. (Here are 2 choke points, so have the AI build units and move them to these positions, if X happens then move them both towards this spot, otherwise hold off using Archers) etc.

Though each unit type can have it's own AI for how it acts, but that would be one-vs-one or other activities, while a collection acting as a chess piece may have different tactics.

I actually rather like Ring Runner's AI, which has general movement AI but then has AI programmed for different weapons and combinations, so it uses nearly all of them effectively. (Though they do tend to run into your ambushes more rather than doing hit and runs or anything else)

Sadly, I found OE started dragging quite slow even by mid-game, let alone late game. The micro never slows down for anything; it just keeps adding up until I'm overwhelmed and say "fuck it" and quit.

Escape from Tarkov

I really like enemy AI in that game, it's like STALKER but 10 times better and they shout some profanities as well. Too bad this game is all about online PvP and developers have no intention to create a single campaign, that would be really awesome and would help bring more people, perhaps they'll reconsider.

Lots of people here saying FEAR but I just completed that game and the expansions and I wasn't really impressed by the AI. It didn't seem particularly good, it was just there. I don't play a lot of shooters so maybe the AI in other games is so abysmal to make this look good by comparison. If FEAR is the gold standard, that's not saying much.

I'm sure it's not the best, but I remember being very impressed by the Unreal Tournament bots when that game first came out.

I lack knowledge in AI programing, but, isn't the challenge to make it so the AI makes decisions dinamically? Aren't they all scripted?

If X > Do A
If Y > Do B
If XY > Do C
If None > D
etcetc

Yeah... It's really heavy mid to late game due to so many cities and armies in the map.
What I made to be able to play "well" was turn resolution down and deactivate "Grass".
But there's a point where the engine can't handle it anymore. lol

What difficulty you've played in?

Also, their Enemy AI:

https://www.youtube.com/watch?v=PaOLBOuyswI

(F.E.A.R. AI analysis) [ Specially 10:55 = https://youtu.be/PaOLBOuyswI?t=655 ]

I played in moderate difficulty but I don't think the AI quality is based on difficulty level. I watched a few minutes of that video and I have a couple of comments. First I don't think I ever saw an enemy open a single door in the game or any of the expansions unless it was scripted. And second and more importantly it's really cool that the game AI allows for scores of possible actions but there's really only a couple that are relevant. Maybe if the levels weren't completely linear they could have tried to flank a bit.

I don't play a lot of shooters but I found the AI in say Bioshock to be about the same as FEAR, granted it's a couple of years newer. Maybe I'm just spoiled and don't expect the enemies to stand still while I'm shooting them or while I'm hiding and if you can achieve that bare minimum you're average.

Nono, it's just a legend I clearly stated it, it originated from that Reddit post quoting 4chan, IIRC, I linked it just as a folklore story.

Additionally the man himself, John Carmak, was asked about Quake ]|[ bots and he replied that no neural AI was coded into the game: https://twitter.com/id_aa_carmack/status/352192259418103809

It definitely is one of the best. It was one of the most advanced at the time and the bots in all the Unreal Tournament games are fun to play against even today. Speaks volumes for a series with the last entry from 2007.

I played F.E.A.R. back in the day and the AI was better than the average, but still in closed, small enviroments with not many hurdles.
S.T.A.L.K.E.R..'s A-life makes NPC coordinate their attacks, for example, while some of them keep you busy others flank you, or they come at the last position you were spotted or heard, they loot the dead NPCs, crouch, sprint, aim, throw grenades.
Additionally A-life manages animals, monsters and NPC in a much bigger enviroment filled with buildings, anomalies height variations

Probably not what you're looking for, but I always found the Chessmaster AI to be quite realistic. I mean, like with everything, it's not "real" AI, but it had enough settings to be able to make a believable opponent (rather than just destroying you all the time).

I'm sure it's quite dated now and there are better chess engines available today.

Yea, it is very disappointing how the development of AI in gaming stagnates.

I was very impressed when playing Stalker: Shadow of Chernobyl for the first time.

I guess it might be better on higher difficulties, but when I played on normal, I was not particularly impressed with FEAR. Might give it a try on hard sometimes.

When I first played it, I thought Thief Gold was pretty impressive, although playing Thief 2 now made me more aware of the limitations of the AI.

One game that wasn't mentioned so far is Rain World. It is a less obvious pick but does an incredible job at giving you the impression of a game world that is alive and filled with all sorts of prey and hunters.