All nontrivial multi-user installations I'm aware of (universities, corporate, ... make it a dozen I've had to deal with) have one thing in common: none of the

All nontrivial multi-user installations I'm aware of (universities, corporate, ... make it a dozen I've had to deal with) have one thing in common: none of them use things like accountsservice, policykit et al. Any extra plumbing, if necessary, is done through PAM one way or another.