Hmmm... me thinks you might not have to. We could probably still download zips/.iffs from sites such as TSR, Sim Gedohns, etc., that still carry Sims 1 stuff. In that case, you shouldn't have to re-install all expansion packs to extract the .iffs - although this would be the only way to obtain the original game .iffs. Maybe the original object files from Sims 1 could be provided to us by the devs/Maxis WITHOUT us having to re-install it? A site download somewhere? or maybe they could ask Stever @ TSR to host the files for download.. This would be a great idea..
Also, this brings up another issue of cc/3rd party objects being allowed, i.e., what is allowed and what isn't. They will soon be allowing us to create our own base meshes, etc., which means 3rd party objects... In that case, the possibilities are endless! I'm looking forward to when we can create our own clothes, hair meshes, etc.!