[rektide]

If you just want to reduce board complexity (what a hobbyost/maker/homebuilder dream that would be), there's lots of package-on-package and system-in-package offerings already!

AllWinner V3s, S3. Theres a SAMA5D2 SiP. Bouffalo BL808 (featured on the Pine Ox64). There's a lot a lot more. I think there's a couple with even more memory too.

Intel's Lakefield, with Foveros stacking, was an amazing chip with 1+4 cores and on chip ram. High speed too, 4266MHz, back in 2020 when that was pretty fast. This is more for MID/ultrabooks, but wow what a chip, just epic: add power and away you go. Ok not really but not dealing with routing (and procuring!) highspeed ram is very nice.

Intels been doing such a good pushing interesting nice things in embedded, but the adoption has been not great. The Quark chips, powering the awesome Edison module, had nice oomph & Edison was so well integrated, such an easy to use & so featureful small Linux system... wifi & bt well well well before RPi.

It would be fun to see DRAM-less computers but I more imagined them being big systems with a couple GB of sram. There's definitely potential for low end too though!