Yeah, the days of upgradable portables are (mostly) over.
And realistically - we aren't in the 1990s-early 2000s any more.
RAM requirements for most people are not doubling every 3 years now and people have far better internet connectivity.
Higher end workload will be offloaded to the cloud or for those who need it, a more powerful, more expensive machine. Fact is, for most of the population, this is enough.
Neo, base model iPad, even base iPhone is plenty of compute for a huge percentage of the market who just want a machine for banking, browsing, social media and communication. Some people need more and that's fine - but there's a huge segment of the population who don't want much more than the above.