Nothing prevents you from using a self signed cert.
It adds security for local deployments as well because you either trust the local CA or your browser tells you that someone has owned your network
It adds security for local deployments as well because you either trust the local CA or your browser tells you that someone has owned your network
With the various web browsers continuing to disallow or blar warnings about "SELF SIGNED CERT", this is not true. There's a lot of _current issues_ trying to access a self signed HTTPS site using mainstream browsers because they know better than you do.
For the last decade or so I've gotten about 1k hits per day on my self-signed HTTP+HTTPS site. Random people will click past the scare tactics of modern browsers re: self signed if the topic is already technical and the demographic understands browsers are stupid. But all these people would be unable to visit under HTTP/2 or HTTP/3 only.