@Diamanishia and @Abbymay2000 I had a real problem with this on more than one Xbox console, I couldn't play Sims 4 for a while at the end of last year on Xbox Series S it crashed every time I tried to play.
But I started managing my game and my saves differently and it's really helped to stop crashing and help with lagging too. It might help you as well, particularly if you have a lot of households, gallery and library items, saves, etc.
🔸Biggest thing is to empty all Sims/Household storage in Build and Live Mode, even fridges. Go back to previous households and clear items in their inventories if you weren't already doing this. As inventories get full it causes problems with performance.
🔸 Carefully manage your Sims/households in Other Households and regularly delete unnecessary random NPCs. I keep it between 80 - 100 in Other Households and I go through them about once a week.
🔸 I keep a check on library storage and clear anything I don't need. Mine is mostly empty except for about a dozen saved things.
It's such a big game and the more content the more it risks crashing so if you can cut down on anything that you don't actually need to store it can really help.
I also only run 2 save games and one is a backup (I don't know about PS as I stopped with PS3 so it's been a while).
I chose to start a brand new game for mine in January but that's not necessarily needed. It was my choice to wipe everything and start fresh because I couldn't play at all. But that was drastic and I wouldn't recommend that to another player.
I eventually upgraded to Xbox Series X about 6 months later but I'd already calmed the crashing and lagging on the smaller console with careful game management.
I hope something here helps! Good luck.