All this is fairly consistent with slave history though.
In America and other countries during and after slavery, there were places that agreed slaves or former slaves were people, and places that did not.
In Gladiator, Russell Crowe went from a high ranking military figure to an entertainment animal; droid bounty hunters might have gone in the opposite direction and “earned” their freedom. I always find it inconceivable how people kept track of who was a slave and who wasn’t back when just about anyone could end up in slavery - my point being that transitions sometimes happened and appearances might not be the best predictors of free or enslaved individuals in such a system.
Yeah R2 does scream a lot. But in the supposedly canon Clone Wars animated series, he gets taken apart while still conscious and doesn’t seem in discomfort.