You're misunderstanding what your original screenshot shows and how many actual backups the game creates.
The game creates one save and five backups of that save, numbered 0 - 4, they do not go any higher than this. Your most recent screenshot shows this:
You can also read Crinrict's excellent guide here on saves https://sims4.crinrict.com/eng/2014/09/save-games/ My saves folder also shows this:
The screenshot you previously posted shows multiple copies of the same .ver1 save backup file:
The operating system has created all of those files in the red boxes because it cannot have a file of the same name in the same location. These file copies can be created by iCloud when it is syncing files and gets muddled. It syncs a file or folder between devices using iCloud and, for whatever reason, syncs it back down to the local machine as a separate file. Finder sees this and instead of writing over the existing local file, it creates another one with the same file name but with an added number so you don't lose data. Your Mac and iCloud appear to have been doing this constantly over a long period which is why you are mistakenly thinking the game is creating multiple save backups when it isn't.
Add to that, because of the nature of the way the game creates backups, which you correctly stated, most of those Slot_00000011.save XX.ver1 (where the XX denotes the numbers in your screenshot) files are in fact different backups because at some point .ver1 has turned into .ver2 which in turn has turned into .ver3.
All of those files will load into the game IF you remove the space, extra numbers and .ver1 after the .save extension. BUT you should only do this by renaming the current saves folder so the game ignores it, then creating a new save folder (with a lowercase s) directly in the Sims 4 folder and moving those files into the new saves folder one at a time, loading up your game and then choosing "save as..." to rename the save. Repeat for every single misnamed file.
I understand now, thank you for explaining. It was easy to be tricked into thinking there's more than 5 backups when you have so many versions! If I turn on my iCloud to start saving the game files, will it revert to what is was doing before with the separate files?
