One point he's making is that people go apeshit over tangs, yet don't seem to give a hoot about most other fish and their space requirements
I don't think that this is entirely accurate (not you, the author). People
would go apeshit over a different fish, but in reality if you're a reefer, Tangs are the biggest and most popular fish that you can put in your reef tank safely (as opposed to non-reef safe).
So questions about Tangs are asked more frequently...I've seen alot of threads about people wanting to place an Angel in a reeftank, but the question doesn't get asked as often because I believe most LFS will tell you while you're browsing that large angels aren't reefsafe.
To put it into perspective. I can only name 1 person on this entire site (off the top of my head) that does a FOWLR tank...That's OhNo. If you put a Blueface angel in a 65g tank, I guarantee that you're going to hear from OhNo, and it will probably be harsh. Everybody else is a reefer,(I'm sure there are more FOWLR, but I can't think of them off the top of my head) so naturally there will be more questions about Tangs.
So it's only natural, that if you ask a question about the most popular fish in the hobby you're going to get ALOT more responses, as opposed to Catherine asking a question about Seahorses, I don't know anything about it, and can't answer it, so I don't respond. But just from the few threads I've read about seahorses, it's my understanding that they need a tall tank, and something to hold onto. That being said, Hannah and Catherine would certainly bring it to the persons attention that they just did something "wrong" because they're passionate about their hobby, and I don't see a problem with it.
Since I've been in the hobby, I've read a ton of threads from people with Tangs that have ich, are dying , dead, or suffering. The common thread from the vast majority of those people is a tank that is between 29-65g. But that's just my opinion ( I have no scientfic data on that, just my memory). Now, we could say that someone with a 29-65g tank, could be new to the hobby and is doing something else wrong to the detriment of the fish. And that certainly could be the case. But I don't know for sure.
Here's what I know for a fact. I've got 3 Tangs in a 180g. they're all alive, they've never had a medical issue (ich, etc).(Knock on Wood) My nephew, (who has more experience in the hobby than I do) has tried to keep 3 tangs (at different times) in a 65g tank that has been up for years. None of his tangs made it, we feed the same food, we shop at the same stores, we do the same care on our tanks.
So I have to respectfully disagree that the Tang Police are ridiculous. If you're going to get into a hobby this time consuming, and this expensive, at least have the common sense to do some research before you purchase, Google is your friend. Personally, I think the research on fish is as rewarding as the actual purchase.
Just my :twocents::D