I was curious WTF you're talking about so I looked up the quote. Poettering was proposing socket-based activation where an infrequently used process, for example, sshd, would be launched when a connection was made rather than idling in the background at all times. You know, like process-based webservers do all the time.
It would have pretty much zero effect on your use case even if it weren't completely optional.
As for the accuracy of the example in the actual quote, excluding phones, which usually aren't running SSH, about half of Linux machines are web servers, another third are cloud machines hosting containers, and another ~10% are file or email servers. The vast majority of those are going to be running SSH for occasional administration. Machines hosting remote X connections are going to be a minority.