My GameCube still works wonderfully.

Yes, I had it, on my launch console, one of the final years of the gen.

I fixed it myself, wasn't that hard. Bought new, good, cooling paste; disassembled most of the console; cleaned up the CPU and GPU; heated both chips with a paint-dryer for a while; let them cool for a day; applied new cooling paste (and wasn't stingy with it unlike how it was); reassembled the whole thing; turned it on and hoped for the best. Lo and behold it worked. And it worked fine, up until this day. I did also paste on some extra feet on the bottom (hard cardboard cubes couple centimeters big) to keep it raised for extra cooling on the bottom. I don't know if that actually worked.

Obviously I didn't come up with the solution myself, I googled it, and figured I had nothing to lose. I also don't know if there's a severity in YLoD's between different people and I just got lucky. But whatever.

Anyway, good luck with yours, I hope it's fixable.

EDIT: Saw your other reply. That's too bad.

I think I can still boot up my ps3 to play some old gems that aren't on ps4. Although the list of those gems got a lot shorter in recent years.

I played all I really wanted before moving on, the only one that I had stopped and later wanted to play was Yakuza 3 or 5, but I will play that on PS4 or PS5 with the remastered collection.