If Nokia hadn't been intentionally destroyed by its board in a romance with Microsoft cash, through a Canadian snake, Maemo would have been a real contender. You can get an vague idea what it looked like from here: https://maemo-leste.github.io/
Also, I don't know what's motivating you to just make negative shit up from whole cloth. Where did Linux touch you?
Look at the TODOs for Maemo Leste, which you just referenced. "Phone calls should work, with audio, when alsamixer is set up properly". That is F-tier user experience. OpenMoko-level garbage.
Still, I think the Jolla Phone would make a great second "toy" phone, if you have the budget for a 500€ toy.