alt Hacker News> But the point is that FPGAs are that accessible today.
They've been accessible for a lot longer than most people think. The original Minimig project (an FPGA recreation of the Amiga chipset, coupled with a real 68000 CPU) started in 2005 - more than 20 years ago! And 15 years ago there was already a complete Amiga core (chipset and CPU) running on the Terasic DE1 development board, the C-One FPGA computer, and the Turbo Chameleon 64 cartridge.
Today's FPGAs are certainly more affordable and more capacious (especially in terms of DSP and RAM blocks) but the biggest shift is that, as you say, it's now possible and affordable to have the complete PCB assembled in short runs, which is a real blessing given that so many FPGAs come in BGA packages.
Accessible for development, sure. Developers and hobbyists are willing to pay $500 for an FPGA devkit, and that's been possible for a long time now.
But, more recently (last 10 years), we've seen increasingly-low-LE FPGAs on increasingly-minimal FPGA breakout boards, with no educational subsidies required to make the boards cheap. There are FPGA boards you can play with for under $50 now; and some <10k-LUT FPGA BGA ICs themselves going for $10-$15. That's to the point that it's just "a thing you can choose to add" to a board you're designing, rather than something so precious that it's the constraint you're designing your board around.