You can absolutely compose in just intonation (JI). It's not terribly difficult, especially digitally as you say. This style of composition is often called "N-l

You can absolutely compose in just intonation (JI). It's not terribly difficult, especially digitally as you say. This style of composition is often called "N-limit just intonation" (for some value of N) or "freestyle JI". However, temperaments allow some composition tricks that are impossible in JI. Tempered systems basically merge annoyingly small intervals that appear in JI, so you can create progressions that would be otherwise impossible. Either way I fully agree that more musicians should be exploring JI and alternative temperaments, and I'd like to believe that it's the future. A lot of people who go down this path fall to the nerd-sniping you mention, and they end up only exploring technique while losing track of musicality. It's hard to find balance.