Publicly-trusted CAs can issue trusted certificates for IP addresses. It's simply far less commonly used, and most CAs either don't offer it at all or only for

Publicly-trusted CAs can issue trusted certificates for IP addresses. It's simply far less commonly used, and most CAs either don't offer it at all or only for enterprise clients. (You might have been thinking about issuance for IP addresses in private/reserved IP space. That is indeed prohibited nowadays, just like "internal names", i.e. domains that don't end in a public suffix.)