Then you found either jerks or communication impaired people. I can see rides where mountain bikes or hybrids would be strongly discouraged or come with a caveat. Specifically if you choose to ride such don't expect anyone else to wait for you.

EDIT: From what I've heard of some need for speed types and clubs I do think something a bit different might be worth creating as a club ethos.

Cooperation. Trying to help everyone find an appropriate ride, trying to help slower riders progress and perhaps most of all providing a good wheel to follow.

I find one thing a bit off regarding the go slow smell the roses idea.

Unless you are very lucky you can't do that nearly as well as a go quick stop when there is something worthwhile. A simple example. Start on the Beach Bike Path South of Santa Monica and be a slow rider. You will never see more.

Be a somewhat quick rider and you will continue onto the Palos Verdes Peninsula. You will see great views that a 'walk any hill' rider will only see if they drive there or spend an hour walking the hill. You just might continue on to the Buddhist Temple and the old WW II gun emplacement near it. Or climb to the top of the hills and have lunch overlooking the golf course.

I'm all sor smelling the roses, but first you have to get to the roses.