We may have fewer expansions, but we have a new category of pack, Game Packs. I think in Stuff Packs we're pretty much equal, and SPs in Sims 4 have at least one game play item while the SPs in Sims 3 were just, well, stuff. :|
Something occurred to me though -- I think I read somewhere that there were concerns about performance issues when they designed DSV which is why it was relatively small (in terms of buildable lots -- it does seem to have a lot of space to expore). Suppose those concerns were mainly for those on 32-bit systems, and the dropping of 32-bit support means that going forward we'll get larger worlds with more lots? It might take a little bit of time to see the results while they test the new limits but there could be benefits in the future.