It looks like this has generally not been a problem.
Anyway, I reinstalled my recapped Performa 475 logic board into the case. Then pushed the PSU connector back onto the board. Then immediately attempted to pull it off again. Plenty of friction but I disconnected it by hand more easily this time. Seems maybe because the PSU was loose this time--not yet set into the case--so the short bundle of wires wasn't restricting grip in the same way. So I don't expect it to be a problem next time I have to disconnect the PSU.
Anyway, I reinstalled my recapped Performa 475 logic board into the case. Then pushed the PSU connector back onto the board. Then immediately attempted to pull it off again. Plenty of friction but I disconnected it by hand more easily this time. Seems maybe because the PSU was loose this time--not yet set into the case--so the short bundle of wires wasn't restricting grip in the same way. So I don't expect it to be a problem next time I have to disconnect the PSU.