I used to think the idea of owning too many games was one of those "impossible by definition" topics, kinda like rational online political discussion.

Now I'm not so sure. Two or three times in the past month or so, I've opened the store without signing in to look at the sales, been intrigued by something, logged in and discovered the item of intrigue already in my library.

Maybe just getting old. Not a complaint, just an observation. (Getting older is still better than not getting older.)

I agree. IMO if you've got a never-ending backlog, you've bought too many games.

You know you've been doing it right if you've finished your entire backlog and can go back to a few favourite games you can always replay until the next big seasonal sale. I've bought games back in 2014 I still haven't touched yet.

It's a good problem to have.

That said, it can be kind of annoying and can cause an utterly unserious sort of paralysis when you're thinking, "What should I play..." Like, I was thinking I wanted to play some kind of RPG when I was done with Ratchet & Clank recently but still have not decided. I'm debating if I should just get the new Pathfinder game, otherwise I'd have to look at the ones I am either partway through or want to start and consider putting it on my plate for a while. That said, recently when I played the Scarlet Nexus demo I thought, "That was awesome, cannot wait!" Some stuff happens, a month passed, got the game and did not feel it anymore and have not since.

But, like I said it's not a bad problem. Sometimes I get a list together of games I need to beat before I let myself move on to newer games (it even worked on a couple occasions). But, then I feel like Medieval II or Age of Empires II and that derails the progress train.

Simple solution:
Delete your account. Create a new account. Enjoy rebuying all your favorite games!

Join the club.

I'm already pretty certain that I have more games than I'll ever be able to beat in my lifetime.

I'm sure there will be a company at some point in the future that will see the business opportunity in selling you another lifetime.

Count me in that category.

Are you positive you have too many games? You have Homeworld: Emergence on your wishlist and right now it's on sale for only $0.99. Alternatively, Homeworld Remastered Collection is on sale for $3.49 and it includes Homeworld Classic.

According to the support page, there are 3465 games on GOG in total -- possibly fewer since this might include bundles, standard/deluxe editions, and DLC. I saw an account here with over 3000 games. The generous patron of giveaways has nearly 2100. And they're not the only ones in that tier. This floored me at first, until I saw it's pretty common here for people to have hundreds of games at least.

If I were to buy everything on my wishlist, I'd have as many games as the OP. On top of that, there are maybe 12-25 games I wish were available on GOG. Other than that, there might be a handful of releases each year that seem interesting. I can never afford games at launch, so even if I do want a new game, it might take years until I can buy it. That's plenty of time to dig into the backlog.

The way I try to prevent my backlog from growing too too much, is to buy games only when they are in their highest discount. And yet, I have nearly 100 games in my backlog. Which is nice, really, because I have some variety. If I feel like playing a point and click game, I have twentysomething games to choose from. If I feel like playing a shooter, I have another 10 to 20 games to choose from. Different themes and styles. Platformers? Rol? Strategy? I´m covered. I will always find something new and interesting to play.

If the backlog grows further than that magic number, 100, it´s when I´ll start to feel worried . :D

Well, enjoy it while it lasts.

Tomorrow your house might burn down along with all your physical games.
Then Steam goes bust and "voof" there goes your entire library.
Then EA decides it doesn't got enough money from you so they force you to cough up more moolah for access to your Origin games.
Microsoft announces Windows 11 drops DirectX support.

etc.

I wonder if anyone says that when they talk about Magazines, or manga, or movies, or paintings... pictures on their phone/camera...

You are clearly deluded. You are not anywhere near having enough games.

I just fire up Windows Solitaire when that happens. ;)

However I did recently subscribe to a giveaway, received a confirmation email and didn't see the games listed in my account - until I did a search and found I had purchased them back in 2011...

I make sure to keep my library small. It feels better for me to see that what I own has been played thoroughly.

Familiar feeling. Only for me, it starts with getting frustrated because it will only let my buy it as a gift :)