Have you started to disable/uninstall packs?

I've not disabled any packs yet. I own all EPs + some extras, so I probably got everythng that adds to game performance issues (which kits don't). My save is from 2014, and last time I counted I played 700+ sims actively. Before I got myself a decent gaming computer this January, it took about 5 minutes to start the game, and the same to enter a house. I have tons of CC, and starting a new save without the CC folder improved greatly on loading times and lag, but I suspect the biggest impact came from a fresh save not involving the memories/milestones etc/like for all my sims. It was like this in my TS3 too, the history/memory in my save killed my game. It never helped that new DLC added more simology and UI. I wish we could opt out simology from certain packs. My first to go would be milestones that I have totally no interst in, abnd that also clogs up the simology panel being rather massive.

In the old days I figured that a few things could reduce my lag. Those where deleting old saves that were no longer important, deleting library lots/sims, making sure there were not too much screenshots and recorded videos in those folders.

I learned to live with my lagging game, performance was not too bad while playing in the same hood and all surrounding stuff was already loaded, I noticed a bad effect once moving focus to a different hood or world.

After switching to a new computer I experience no lag on highest settings, but there exists no such thing as a paradise: The new computer has much smaller harddrive than the old one, so I already need to tidy up. I also realise that I might need to skip a few future packs. The fairy one made it easy on me, because I'm totally not into that theme, and it seems like a different game compared to my running TS4 universe. I made the dicission when I realised that I did not actually know that we got plant sims...  Anyway, spending this much time on my sims game, I figured it would be worth it investing in a better computer,