Most of these were just games I received either for free or were in grab bags and happened not to interest me. It may or may not be a shame, I have not tried them.

One of those is on my wishlist. I wonder how many other people own games that I want, but they won't ever try them.

Oh? Which one? If I could, I'd give it to you.

Ha, don't worry about it. I have a sizeable backlog and an overly large wishlist. I was just remarking that one person's trash is another person's treasure. And the game is Jotun: Valhalla Edition. Games with artistic flair in abundance tend to catch my attention.

Edit: Also, I got the first two Syberia games when they were on giveaway. I intend to play them one day.

Many have Jotun because it was a freebie in 2017. And agreed about the art aspect.
There is a point where it considers that you have enough information to reach a conclusion and you have the option to "finish" it, and also the point where you discover all the videos (which is possible without cheating, I did it). So it has an ending, but not a conclusion, since that's left entirely to the player.

And to answer the OP, see attachment. Tags should explain all.

Holy cow! 73 out of 179 games. Did you end up buying too many blind bags too?

Roughly 50 of those games have been given away as free in some form or another. and that is only counting the giveaways that I am aware of.

Much better as a work of art than as a game -- yes, that tends to be an issue with these types of games.
How did you end up with both Shadow Warrior Classic Redux and Shadow Warrior 2 but no interest in them? Were they also on giveaway at some point?
But 25 out of those are tagged Completed.

Yes to both.

Shadow Warrior Classic Redux

Shadow Warrior 2

This is a good suggestion for improving the personal games library.

Aren't ending and conclusion synonyms? I'm really curious about this one because in this case I was assuming them to be so. Besides that, I didn't remember the game giving the player the option to "finish it" so thanks for bringing that out; I thought no video piece in 'Her Story' was the definite one to provide an eureka moment to the player, so that's what I was trying to convey, that the game ends the moment the player has figured out the mystery, not when all the videos have been watched. But hey, I saw you hid the game, how dare you! :P

The only purchased game tagged as not interested is Might and Magic 2, and that's because my first GOG purchase was the M&M bundle and I abandoned the first because of the lack of free saving and that also applies to the second so didn't bother to try it. The rest are all freebies, though a couple came with other games. Only stopped grabbing everything given away just because it was free when they made that automatically sign you up for newsletters, made me think about it for a moment and realize there's no reason to get things I know I'll never touch under any circumstances.
Hid it because I finished it. Reviewed too.
And in that game they're different. Like I said, for one you can reveal all videos, which should count as completing it by any definition, the game has no more to offer you, but there's also an earlier moment where you're given the option to "finish", yes (and something is revealed). It just never tells you what the correct conclusion is, that's entirely up to you.