Hearth & Horn

You're on to something there.

I do think there's a dynamic worth poking at: on average, a functioning group needs/wants a new person less than a new sincere seeker needs/wants the group.

And adding a new person is, on average, dozens of hours of effort on the group's part (probably double or triple what the new person is putting in, in the early stages, and then evening out to about the same level of effort on both sides, because there's a bunch of logistics load on the front end.)

Which is fine if there's a great fit, and a lot more complicated in the majority of cases when it's not (see my previous comments about statistics.) And the cases where it goes really badly can be actively destructive to a group that was otherwise functioning and doing things everyone in the group enjoyed/got stuff out of.

I think the space for experiment also varies a lot - I'm really up front about the "I want to do the practices of my tradition, we may occasionally experiment with different approaches as a learning experience or to develop skills, but if you're not interested in this set of stuff, we're not a good fit, because this is the set of stuff I've decided to spend my time and energy on, and those things are limited."

(Which I'm up front about, because like you say, that seems fair.)

There is a pattern of people coming into existing groups and wanting to change lots of things, and I think that makes groups extra wary of it happening again, and taking defensive postures against it.