It can't really be called the spiritual successor of the Nokia N900 if it runs Android. What made the N900 special wasn't just the hardware, it was also that it was running a traditional Linux environment, which means you could use that physical keyboard for all the hacking you can do on your desktop computer.
Termux. Also, all of these devices (F(x)tec Pro1 X, Planet Gemini/Cosmo/Astro, ...) run a myriad of OSes, so if you don't want to run Android you got alternatives (including AOSP-based). As does Nokia N900, just not out of the box back in the days.
