I remember in 2007, buying my first MacBook. It came with an enormous 2gb of RAM. I asked about upgrading it. The guy leaned in conspiratorially and told me that Apple’s RAM upgrades were a rip-off, and that I’d be better of buying it elsewhere. So I did, for half of what Apple were asking.
This is a grift that Apple have had for far too long, and there’s a part of me that’s convinced that their move to soldered RAM was to stop people upgrading after the fact more than it was about SOC efficiencies.
iOS (and android) is also propped up by phone payment plans. My carrier offers me a new phone every two years for like $10/month which works out much cheaper than buying the phones outright.
If they were offering a Mac for the same deal every two years, people would upgrade those more often too.