Most updates fix the game we are playing and do not require us to start over. I've been playing the same Saved game for at least 10 years. Since Get Together came out. Yes, this requires some tending, but it's certainly doable.
Back up your game frequently.
Test updates with a new vanilla The Sims4 folder not your regular TS4 folder.
Keep a separate TS4 folder for checking out mods, CC and Gallery downloads.
Repair/reset your game as soon as you see something odd. Use "save as" often.
There's lots more advice out there. Google it.
There's lots of good stuff on Crinrict's Help Blog.
I beg to disagree. (1) From Nov. 4 update (150+ bug fix) the bug where sims wear hats when naked does not apply to current saves. Despite not stating in the official update log that only new saves will be fixed. (2) The present update from Dec. 3 where they fixed the underwear on naked sims was not applicable to present saves, also despite not mentioning that fact in the update log. Only to be found in the comments section that it is in fact not retroactive. I know because I was the first to make a post about it on both instances.
This begs the question, which of the bug fixes is retroactive and which one is not? Because it's never really specified consistently in the update log.
As to "tending" a save. I also know this because I made a post with a 10+ list of what you need to do if you wish to carry your old save into a new one. But as a player, I really shouldn't be doing that don't I? I also shouldn't be here in the forums to report bugs do I? I should just be playing the game.
Only in The Sims have I experienced where fixing the game is the status quo and reporting and upvoting a bug post is a duty to make the game better. In other games, I just play.
So when a player criticizes the developers for the poor experience, you don't offer a workaround. That is not your job. Instead, you help to voice your concerns as a consumer. Because we are on the same side of consumers and they are on the side of seller. Believe me, they are not on our side. They just want our money. That is an objective statement of fact and not up for debate.
Final note, a bugged game that provides a defective feature that was advertised violates the seller's implied guarantee of fitness for a particular purpose and is actionable.
