Hey y'all, just wanted to share this potential tidbit of information. I'd been having a lot of problems with lag in my game recently--sims would 'freeze' in the middle of actions while time ticked on, requiring me to pause for sometimes five minutes until they 'unfroze'. There was no common thread that I could find--it wasn't tied to some sim in the household changing emotions or doing a particular activity, it just happened all the time.
At the time, I thought it was because I was playing with an i5 processor and 8gb of ram. I recently got a new computer with much better specs, but the issue persisted. I lowered my graphics settings, removed all custom content, repaired my game, and reset my sims 4 folder, then only loaded the one game's save file, testing between each attempted fix, and nothing helped.
On a whim, I ended my club gathering, and I haven't lagged since. Now, I usually play with a family club, even if I don't have skill perks, just for the rally the troops perk. I love it, especially since the book of life doesn't work anymore. I didn't notice this lagging issue until about halfway through gen 2 of my immortal dynasty, and I'd basically been in a continuous club gathering since the beginning, and had accumulated a great deal of club points by then.
I have to assume the issue was related to the club gathering, since it stopped right after I ended my gathering. I think it's possible that having an 'old' club, or a club with a lot of points, may lag the game. I just thought I'd let anyone else who plays with family clubs know about that, since I didn't see this as a potential lag cause in any tip threads, in case you're having a lagging problem that won't go away, try ending the gathering for a sim day or two and see if anything changes.