My VPS provider is running a promotion where I can get up to 5 additional public IPv4 addresses for a one-time cost of $25 each. I have always only used a single public IP address per VPS. Would there be any advantage of having additional public IP addresses?
I know some people do not consider a VPS self-hosting, but this is the most relevant community I could think of and the question is also applicable for homelabs as well.
By “modern” do you mean “the late 90s”? HTTP 1.1 was adopted in '97 and allowed for the host header. NAT and port forwarding have been around since '94 - 2000ish.
Many services worked on any ports at the time as well. SMTP and DNS are probably the only ones that were (and remain) difficult to run on non-standard ports.