To play around you can either use Element X or go to app.element.io/#/welcome and use the Element web version. It’s basically the same client. Then create your account with matrix.org - you should be able to create your own space + sub-spaces + rooms to play around with inviting users, get familiar with permissions, etc. There might be limits with video / voice calls - not sure about the public, free matrix.org server.

If Matrix is a good fit you can then look through the offerings of some of the respected hosters listed here: matrix.org/ecosystem/hosting/ Then you don’t have to do everything yourself. They will maintain the infrastructure and your base installation and you can focus on being just the super user / admin and build your community.

IMO the only real “hurdle” compared to traditional apps is that in addition to your username / password you also get a “recovery key”. That’s the key for encryption and people are not used to having an additional key. If you lose that key you can still log in and see new conversions but you will not be able to read old conversations that were encrypted using the old key. A workaround for your community might be to not enable encryption in your community rooms (when creating a room you can decide if its contents are encrypted or not). IMO totally worth the little bit of extra effort, but yeah - not something users are familiar with.