That doesn't bode well for the number of people who would use or care about such a feature.
Agreed. tcp_wrappers predates the widespread availability of easy, effective software firewalls. Back when services listened on 0.0.0.0 and if you were lucky you had ipfwadm, tcp_wrappers made a lot of sense. Now it's IMO a pointless layer of additional complexity that no longer serves a purpose.