(ossia dev here) yes, we have quite a community mainly due to having a big push in funding in media and specificially music & audio research labs in the 80s / 90s with places like IRCAM, GRAME, SCRIME etc. :)

Also see IanniX (https://www.iannix.org/fr/) which is another OSC sequencer from french developers & researchers and Open Stage Control: https://openstagecontrol.ammd.net/ (yes, also french ;p)

@op: ossia has some support for PTZ cameras (mainly through NDI) and MIDI/HTTP/WS/etc..., I'd be curious to know if it would fit your bill. Definitely hooking some MIDI control to a PTZ movement should be a matter of a few clicks at most but I don't have a PTZ camera plugged in right now to make a small video.