You can't change attitude with a fingersnap solution, as that's what this is, an attitude problem. When the reaction is almost an abhorred shock that you're actually, and I mean actually, are playing a mode just for the mode upon being asked why. Attitude problem. Justification for that contempt typically includes something or rather "game has nasty netcode y u do", "pvp is bad in general". Acknowledgeable? Sure. But still all subjective. I think why does netball even exist when there's basketball? Which to me is just a better version of the same game, but if someone is getting enjoyment out of it who am I to judge? Some people might play both because they just happen to enjoy ball games (and netball is even on the rise where I live...) That's my stance with pvp, and why I partake of it even in this game. I like to fight people when it's an option, even if the venue is merely passable. At least it isn't p2w automated, that's a line drawn. I can still move freely and have real-time control over my actions even when there's a hardcoded delay.
Either way, personally, my motivation levels are very weakly influenced by rewards. I'll stop when I'm no longer having fun regardless of whether or not I've hit a milestone, much like how I've quit raiding and pve for the most part in this game (until it might pick up again in 8.0). That being a seeming minority take... to put it plainly, is flabbergasting (the playing for enjoyment angle). But you just can't change something inherent at the flick of a switch. It's frustrating that others can seem so fickle in their NEED for a tangible reward in order to do anything, but it is what it is. It makes everything more bland. But I guess that's a reflection of the mindset of someone that would... yeah, focus on clicking tomeliths and not actually fighting in a battleground just to make number go up on the "achievement" panel. Bland.
Game could always use more pvp variety too, that would help a bunch probably. Finally, as a sidenote... I'm also not sure why "playing for fun" and one's output being of a higher standard can't go hand in hand neither. That I can't be playing for fun simply for injecting some finesse (p.s. not in a premade). It's such a strange logic, but one I've seen invoked.