A level of discussion that some may regard as professional is both
allowed by charter and explicitly expected. If people don't want to
join in a discussion that others do enjoy they can refrain.

This may be true in theory but doesn't work in practice, as we all
know. There are just as many "professionals" criticising "amateurs" as
vica versa, in fact mutual distrust and interaction seems to be the
mainstay of the group.