Answer HQ is a community based help site, we sadly don't make business decisions or design games so we can't help you with "fixing" any of that.
Anyways, my guess would be that it's because there's not enough money in creating a Mac edition (at least until the pc version is finished) and The Sims 4 is the way it is because it's not any of the previous game with better graphics, it's a new experience, they have included some new things and didn't have time to include all the old, that's how sequels normally work.
Now, if you want to discuss it further The Sims 4 has an excellent forum for just that here: http://forums.thesims.com/en_US/ - there the developers might even actually read it.
Oh, and just get a bigger harddrive for your Mac and there is plenty of space for Bootcamp 😉