Having played online for a long time, yeah, it's not unreasonable. I used to be a "hey, you want to play? Come on in?" kind of host. I got burned so many times that now, I am very particular about who I game with. I am far more likely to walk away from a group than I was, for sure. And, when talking to prospective new players, I really do try to outline expectations.
It makes sense really. We're going to be spending dozens, if not hundreds of hours together doing something. We really should try to make sure that everyone is at least close to being on the same page.