Pretty much. The bugs and performance issues after you get two generations in make it unplayable for me.
I love Sims 3, but I admit I only play it after adding mods to make it more playable.
I use these mods:
Nraas Overwatch - this mod will "clean up" the neighbourhood at 3am in-game time every day, and helps to remove accumulated junk around the world to help the game run smoother for longer (e.g. deleting unused cars left around by townies, turning off stereos and TVs, resets sims stuck in a "broken" interaction). Also recovers any "missing" sims that disappeared due to a bug.
Nraas ErrorTrap - this mod "traps" errors to stop the game from crashing and corrects data corruption that can make the game unplayable.
FPSLimiter (requires 3Booter) - this limits the game to 30 FPS. Normally it can go above 100+ which can fry your computer and is not necessary for playing the game. I think some modern video cards in computers can do this by themselves though, so the mod may not be necessary (e.g. the AMD Ryzen/AMD Radeon on my laptop can also do this I think).
I also use other mods from Nraas like MasterController and Traveler, but more so for gameplay style rather than fixing bugs (although Traveler can help with bugs relating to sims arriving in holiday worlds).