Look at the state Maxis left Sims 3 in. Now ask yourself why you think they'd do any better for Sims 4? The only reason I can think that they may do better is because consoles can't use mods. Two-to-one there will be a Sims 4 mod workshop (or whatever it's called) on for xbox soon.
Maxis, since Sims 2, has required mods to fix their games. Sims 3 is far worse than Sims 2, and the couple of patches that have been released since Sims 4 has been released have mainly been to connect Sims 3 to Origin (fortunately, those updates is avoidable provided you didn't buy your content directly from Origin). Think about it -- they released patches after Sims 3 was no longer in production to try to force people to use their storefront, but they had no interest in all in attempting to fix some of the bugs.
It doesn't matter whether I want new content or bug fixes -- bug fixes will be incomplete, and more and more packs will be built on a buggy foundation leading to more instability.