I think ajduplessis nailed it in his post on page 1. There is a significant subset of the community that regards modern basic OW (and AOW) training as excessively watered down with too little content (e.g.: little Rescue training beyond towing somebody by their tank valve), run too fast and passing students for demonstrating a skill 'more or less' maybe one time (perhaps while on their knees, not while in the water column) rather than demonstrating and achieving mastery, then turning these ignorant incompetents who 'don't know what they don't know' to endanger themselves, buddies, dive professions who get them in tour groups, and even our hobby by inviting governmental regulation when they get themselves killed. Oh yeah, and the coral reefs they accidentally kick or even crawl around on.
Not saying I go for all that, but I have seen that sentiment. And yes, I think there's a sentiment that some instructors are the scuba teaching equivalent of 'puppy mills,' as opposed to 'pedigree competent diver breeders.' Naturally a 'puppy mill' can mass produce a lower end product cheaper. Mainstream agencies are seen by some as sharing some of the blame for all this. I'm not saying I buy into all this, but there it is.
Other people already pointed out when you deal with the public, you get some frustratingly rude, boorish or just off-putting people. To a lesser extent, I've noticed scuba is billed as having once been the province of adventurous type folks. I'm thinking Type A personalities, etc... Overtime, it's become more 'consumer commodity' like. You've seen the term 'Vacation Diver' used on the forum, I imagine, referring to people who dive once or twice a year (or less) in tropical destination with pretty reefs & fish, and that's it. Have you noticed on the forum people speaking of cruise ship passengers in disparaging terms like 'Pod People?' What's it call to mind, a pot-bellied 40 - 60 year old American tourist in a Hawaiian shirt & Bermuda shorts with a camera on a neck strap standing about clueless about the local culture, etc...? Well, I think that's the way some people unconsciously think of the mainstream middle class, a group that the dive industry's growth, simplified 'modular format' and guide-led group dives in the Caribbean cater to. A lot of this is speculation on my part. I don't know what postings your impressions were derived from, so I'm doing some guessing.
Richard.
P.S.: Disclaimer: I've been on 3 cruises! Go Pods!!!