Pixel 4a fits most of these requirements but its almost 5 generations out of date and has no SD Card, + the extra security requires you to install a custom ROM like Calyx, Graphene, Lineage etc. and the hardware vendors no longer support them, so you dont get hardware updates, only OS.
You can use /e/OS or Muerena or whatever its called now on the 4a though. It kinda looks like iOS
As far as I can tell by skimming Wikipedia, no. Its based on something called OpenHarmony, which itself was based on something called LiteOS Source: https://en.m.wikipedia.org/wiki/OpenHarmony
Edit: Looks like HarmonyOS used to be based off of Android, but has transitioned to OpenHarmony extremely recently. “It replaces the OpenHarmony multi-kernel system with its own HarmonyOS microkernel at its core, removes all Android code and supports only apps in its native App format.” https://en.m.wikipedia.org/wiki/HarmonyOS
So while you would’ve been correct a few months ago, it appears this is no longer the case. I can see why my comment would’ve seemed stupid at first.
Carrion by the Divest team works pretty well as a FOSS spam blocking solution in my experience. Another factor is I changed my number a few years back and I dont give it out to anyone unless necessary. I bought a “free” Sim from a company called FreedomPop for when I need to give out a number and I dont want to share my real number. I keep the Sim off Unless I need a verification text.
I agree with you but also have you tried Heliboard, FlorisBoard, or FUTOKeyboard, Theyre all very decent FOSS* keyboard projects. I like HeliBoard myself.
*FUTOKb is Source available