I haven't played the game in a while. I'm reinstalling as I speak as I type this. I've been MMORPG homeless for a while. I always eventually come back to games to check out the state of the game. I check out the forums to get a general comprehension of the state of the game as well.
The issues in WvW, are not exclusive to games like GW2. Most MMORPG's fail to address the issues in their large scale PVP combat. ESO is an example, GW2 is also an example.
While there is niche issues such as siege issues or general profession/class issues. Most people will complain about combat itself in large scale-combat. The #1 complaint always ends up being zergs, or in GW2, they're referred to as blobs.
Blobs/zergs are annoying, and reward zero skill-gameplay. They crush smaller groups, solo players, and overwhelm in siege warfare.
The same thing always happens in these MMORPG's. And you want to know why? Game Developers are too afraid to allow players to have powerful Crowd Control. That is the key to defeating zergs/blobs. In past games like Dark Age of Camelot, which is historic for its large-scale PVP/RVR gameplay, and has received more awards for their RVR than many present MMORPG's. Players in that game could be a smaller group and overwhelm zergs. People would even build 8-man groups dedicated to zergbusting. It was only possible because the game developers allowed classes to possess powerful crowd control. Whereas, most gamers today will cry foul when experiencing such powerful crowd control. Gamers and game developers are their own worst enemy in this regard. "Balance" is a relative term in gaming. One player may look at such powerful crowd control as game breaking. But, as part of that double-edged sword. That powerful crowd control is a necessary tool to allow one dynamic of combat to be put in check. Specifically, that dynamic being zergs/blobs. Smaller groups having the means to overcome overwhelming odds is balance in large-scale PVP/RVR/WVW. In DAoC, those smaller groups had to get the element of surprise or be fortunate enough to get their crowd control off first in order to overcome a zerg. But, because it was possible, it allowed such balance to occur. Zergs could still wipe out smaller groups. But, smaller groups had the means to fight back. You lack that in GW2, ESO, and many more MMORPGS. As a result, who brings overwhelming numbers is generally the winner and it becomes a DPS race to zero rather than a fight of skill, tactics, playstyle, or group composition.
They run afoul because you lack the crowd control as a means of counter-warfare. In DAoC, a pac healer would drop an AOE Mezz on a zerg, then an AoE stun. Then the casters would PBAOE the zergs down. You can watch oldschool DAoC videos of groups like FUN II beating entire zergs as an 8-man team. You can watch famous DAoC groups like Team-Wizzy, who was literally 1 guy boxing multiple accounts with PBAOE Ice Wizards and 2 additional players to heal and provide minstrel speed. They would down entire zergs, and crowd control was the key to doing so. It obviously had to be executed correctly, but, it was the pinnacle of large-scale RVR balance. WvW/RvR should not be a battle of "the most numbers wins." Smaller groups should be provided the toolkit necessary to overcome the odds. WvW will not be fixed until THAT is a reality.
Good luck doing that in GW2 and most modern mmorpg's. You aren't given the toolkit to make that a reality. And yet, DAoC had the best large-scale PVP combat of all time and won the most awards consistently for nearly 2 decades to prove it.