I wonder how much the "evangelism" thing comes up with regard to other instruments? Most of my musical friends are guitar/bass/drums/piano and they definitely don't go to "bass festivals" or "piano retreats" or hang out on online forums (although I know those do exist). But what about, say, French horn players? Recorder players?? Just thinking out loud
Just some unsorted and unstructured thoughts on those (and related) topics:
I think that is in part just a cultural aspect that some instruments are surrounded by and that others lack (I'll touch on possible reasons in a moment), especially the festival bit. The ukulele is more strongly associated with a certain mindset, attitude, or spiritual viewpoint, in part influenced, or perhaps created, by the Hawaiian approach to life (I put this very broadly).
Perhaps it is also a result of the "lack of respect" as a serious musical instrument that the ukulele sometimes seems to suffer from in the mainstream view. I don't know how many times people said to me "I didn't know you could play
that on a ukulele!" when I shared with them a Jake video or classical piece. It's very frequent. You'll almost never get that response when you show someone a classical piano performance or a rock guitar solo. When groups of people feel "excluded" (too strong a word), they look for like-minded folks to spend time together with. Hence the festivals and clubs, which furthermore assist in finding others. Like nudist beaches, just with clothes.
I also feel ukulele players are more laid back and don't take themselves too seriously, which in turn means they like gathering with others in a not-so-competitive setting. The ukulele is a very social, accessible instrument, so it appeals to people who are social and perhaps a little more fun-oriented than "performance oriented", that is, they don't have impossible ambitions and are less toxic (the UU forum is one of the least toxic forums I have ever encountered). If that's true to a larger degree, and I don't know if it is, it also means that people who are drawn to it are different (as far as their preferences and social desires are concerned) from the people who are drawn to a bassoon. The ukulele somehow oozes "fun" in a way that is not common.
French Horn players are less likely to meet up for a beach festival and start "strumming" (whatever the equivalent is on a French Horn
) -- same with flutists, I guess --, because the nature of those instruments doesn't really lend itself to spontaneous, laid back "social music making". Grand pianos are also a lot less portable, and much more expensive, which also makes them less suited for a "piano festival" where everyone brings their own instrument along. Some of these instruments have a much higher entry barrier (in terms of cost, but also in terms of "getting started", including expectations to oneself and from others).
The ukulele checks a lot of different boxes (technical, financial, social) that make it a non-threatening, affordable instrument for people who do not first and foremost define themselves as
musicians, but as
people who like to make music, either by themselves or with others.