I agree 100% with you! horses have gotten a bad rap for so long!
I hear all the time that you "have" to keep seahorses in a species tank. That is the easiest way to do it if you don't have more information but there are plenty of fish that you can have with seahorses. The information on what fish live well with them and what fish could with some work needs to be readily available to people. And really the only special equipment you need to keep seahorses beyond any other type of saltwater fish are foam covers for the power heads, about $2 worth of extra equipment.
I mostly agree with you here. When I give advice to 'newbs' or people just getting into horses, I think they absolutely do need to be in a species specific tank. This is because of the reason you mentioned before, they are different to keep. Once you've kept a pair for a few months, you get the hang of things and understand exactly what types of tankmates would be ok for cohabitation with your horses. In the context of the conversation, how can hobbyists help the seahorse population, I think that horses need to be in their own tank, you're talking about breeding here. Pregnant males and fry thrive better when other fishes aren't trying to eat them or bug them.
I feel like I've stepped up on the soapbox many times to try and dispel the notions that horses are wimpy, high maintenance, or otherwise fussy creatures. Actually, they are quite hardy and tolerant creatures.
I do, respectfully, disagree with you in the big picture though. I believe, in my opinion, that a sudden increase of hobbyists adding horses to their tanks would cause overfishing in the wilds. If we could get a sudden increase of informed breeders, we could make a difference!
C