Your not alone in feeling this way! I have bought everything twice (PC & Xbox) and I'm regretting it. I keep falling into the trap of hoping each expansion or pack will improve my experience. Like you I'm at the point of, why am I doing this?
Saw an interview with one of the heads and she said they have a hard time balancing the game in terms of players who like ultimate control and players who like things to happen to their sims organically. I like to "Play With Life" and so therefore like things to happen organically and then in turn I have to respond to that as a player, just like life. Starting to realise the Sims 4 will never be that game. With the news that there will not be a Sims 5 has made me realise that the franchise I loved has become a dolls house which I don't really want to play.
There is so much setting things up yourself. Too many warnings before something happens to your sim that it not a suprise, like none of my sims die from anything other than old age because I get several warnings that they might die so obviously I then save them as I got several notifications. I could let my sim die but this then feels like planing, planing out death in a life simulation isn't fun. Even if there was an option to remove these Immersion breaking notifications it would help the player experiance as things like death and divorce would happen and be suprising. I've seen theres a mod by Carl that creates a kind of 'hard' mode which I think would be good idea for the team to look into for player who like to be challenged.
Visually the Sims 4 is beautiful with a build and CAS mode that is far better than it's previous generations but I no longer feel like I'm playing a game. I was so hopful for the re-release of Sims 2 that I could leave the Sims 4 behind, but I had so many issues within the first hour of playing that returning to a previous title isn't an option. I think I need to stop listening to influncers and worrying that I won't be able to download their build off the gallery if I don't own all the items (I'm looking at you Kits and pre-order bonuses!). It's a tough pill to swallow but I'm slowly starting to accept the fact that Sims 4 isn't going to become the Sims title I wanted and that no ammount of expantions will be able to make it so.
What does this mean moving forward? I need to stop buying, unfortunatly I preordered Bussinesses and Hobbies before I realised you probably won't even be able to shop at the stores you create or download off the gallery as a customer unless you have an owner (like issue with get to work retail since For Rent released) again even more setting up for me to do as the player (setting up is not gameplay). With no Sims 5 in the future, EA putting their efforts into multiplayer (i'm a simmer I'm antisocial) and transforming the game into what feels like a live service mobile gaming model, I guess like you I need to step away 😓