I agree... the "pvpers" want to have the dragons nerfed, because they always want tamers nerfed. The problem isn't the dragons or any other pets. The problem is that there are a few game mechanics that are highly abuseable with ANY pets.
If your strategy to fix the current imbalances is to nerf pets, you have to nerf pets down to the point where they are completely irrelevant in both pvp and pvm. The problem is GAME MECHANICS, not pets. A pet being controlled perfectly, but without the use of these abused mechanics is not only balanced, but actually at a disadvantage.
The game mechanics I feel imbalance tamers the most are:
Pet Balls
Ninja Forms for run speed
Archery dismount (an issue in conjunction with pets or gank squads)
perma nerve strike (done through an exploit)
As long as the pvper being attacked can stay mounted and can't have a pet called in directly on top of him, a pet is a minimal threat at best. Pet balls allow tamers to bring their pets into the combat on whatever terms the tamer chooses, which doesn't allow their opponent to take any recourse.
IMO pet balls break are the #1 most abuseable item in pvp today. I think pet balls should work like a summoning spell (cast time and interruptable) to prevent players from summoning pets as part of offensive combos. Pets aren't nearly as dangerous if they can't be called in as part of a combo...
Ninja forms are mostly balanced, but the ability to repeatedly summon a pet while chasing a dismounted player down at mount speed is a SERIOUSLY broken game mechanic. You can't have ANY reasonably strong pets in the game and have them be balanced with a game mechanic like this. If pet balls are balanced, ninja forms also become balanced. I don't think you should be able to use pet balls while in ninja forms (just like any other summoning spell). I think a nerf to disallow use of the pet ball while in a ninja form reduces ninja forms to being a quick escape mechanism instead of a "run the guy down for a kill" mechanism.
Dismount in its current form is just cheesey. It encourages gank squads and does a lot of damage to pvp. I'm ok with dismount as a game mechanic, but something needs to be done to balance it more. The problem with it is that it effectively flags someone as the guy to gank. Without it, pvp can become all about running all over the place. Perhaps dismount could be changed into being an attack against the stamina of your mount, so a few successive dismounts drains your mount's stamina and knocks you off. The other way to go with this is to create more incentives for unmounted combat. IMO, mounted combat is difficult to balance because mounted speed is so much faster than unmounted speed. In the early days of UO where not many people rode mounts, pvp was at its best. I attribute mounted combat to being the biggest killer of pvp balance in UO.
I think there's plenty of room for a dialogue on how to balance the dismount mechanic... I just tossed a couple ideas out haphazardly
Perma nerve strike...
There's an exploit that allows someone to hit you without breaking your nerve strike paralysis. This allows somene to run around mounted on a cu or hiryu, stun you in place and kill you at their own leisure. This exploit gives legitimate tamers a bad name. Just like casting sploits give legitimate mages a bad name and speed hacks give pvp a bad name.