I saw this about a year ago, but nothing seems to have come of it since the board maker switched to some bigger Risc-V chipset:
https://www.cnx-software.com/2021/03/19/sigmastar-ssd210-tiny-dual-core-arm-cortex-a7-soc-64mb-ram-rgb-display/
It would be great to have a tiny linux board, like Raspberry Pi Pico size or smaller. The amount of ram and cpu on that chip is fine, don't need 0.5gb of ram. TF slot or tiny BGA SSD would be good, of course.
You might like the Groboard
https://github.com/Groboards/giant-board-design-files
https://www.crowdsupply.com/groboards/giant-board#products
Maybe Vocore2? Tiny OpenWRT board based on MT7628 router SoC.
https://vocore.io/
Pro:
MT7628 is ubiquitous (millions of cheap WiFi routers are based on it), Sigmastar SSD210 is like 'unobtanium': I can't find it in stock even on Alibaba and Baidu.
Con:
MT7628 is less powerful, 2x580MHz vs 2x1Ghz.