Funny thing is, TBL anticipated this years ago when registering the service names. Read the assignment notes at https://www.iana.org/assignments/service-names-p

Funny thing is, TBL anticipated this years ago when registering the service names. Read the assignment notes at https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=http https://www.iana.org/assignments/service-names-port-numbers/... - yes it's talking about DNS-SD specifically but the remark generalises to all service discovery, basically setting the expectation of different service names based on intended use. API endpoints tend not to be apex records, indeed are characterised by using a label of "api" or similar which doesn't automatically conflict with other services, certainly not in the common case. It'd remain a violation IMO to use a host name as a service selector but in practice they could continue using address records for many years of transition.