@solariiknight update on that, it appears the answer is "no", #PineBook is not fully freedom respecting :(
https://trisquel.info/en/forum/trisquel-arm-pinebook-pro-running-trisquel-trisquel-touch

FWIW #Purism has been accused on the same forums of having similar issues:
https://trisquel.info/en/forum/librem5-and-why-i-am-no-longer-interested