The Sims TeamI strongly disagree with your assessment that DLC is causing the game to crumble. I read this as a endictment on players who bloat there saves and over use mods. File size can be a problem even for people who only own Base Game. If every lot in your game is packed full of high polygon count CC your game is going to fall apart at the seams. Modders and CC creators do not at all adhere to best practices in how they create their content. They don't have to because there are absolutely no consequences for creating extra high polycount swatches FOR THEM. You don't see players blame CC/mod creators. Ever. They blame Maxis. Frankly if it were up to me I'd fully support Maxis banning the use of CC/mods. I think every game that allows it suffors for it.
First of all, File Size is not the same thing as file complexity. The Issue is save complexity, and yes I have been effected using ONLY the base game + the Official Packs; If even the Maxis/EA Data is getting corrupted I don't think Modders are the real issue; after all, all code can do is what it's made to do; even in this age of (supposed) AI, we still have yet to make a program that can fully automate the coding and testing of said code completely, and for good reason: It requires a human touch, like a leader behind a throng of followers. The truth is, the save's complexity is already quite high owning all the packs, and while this itself is not a problem, it can complicate the task of trying to decipher what happens when something goes wrong; I think when all is said and done we will learn that the "save corruption" doesn't come from a single source, but rather many interacting variables.
Personally, I look to other gaming platforms and see things like Unity Vulnerabilities that are coming out of the woodwork and think "Could this be related?", I think atleast one of the problems has become the human X factor...the fact that no matter how well created a program, the programmer/designer can only anticipate certain usages in advance, but we all know there are usages that we think of later...that's the kind of situation where errors get made, and it's for a want of a better term natural...the world exists far beyond binary.
Also with what little experience I have with coding (which is probably more than you tbpf seeing as I am a professional scripter and a hobbyist modder), polycounts are not rendered in the data structure of a save...they linked files cross-referenced by the main (data) save, which then when loaded into your game recalls the cross-referenced image data and loads it on your GPU at that time; the corruption of data is in no way tied to visual performance.
