Granted, there are earning restrictions on OW member programs, just as there are with *A and ST. However I've never had any real difficulty making sure that the flights I book (virtually always discounted economy) are in a booking class that earns at least some miles and status. The airlines all publish their rules fairly clearly, so it shouldn't be too hard to avoid mileage issues.

A lot of it comes down to glass half empty/full. I think some people expect airlines and alliances to effectively be charities by giving them full mileage on the lowest possible fares.

My approach has always been to identify what I value most about the airline/alliance and make it work for my situation and travel needs.