Current PvP TTK design is bad for the game
Issue
Having experienced PvP in-game for a few weeks now (1v1s, group vs group, raid vs raid), I can safely say the short TTK design is as bad as we feared.
Reasoning
Short TTK (even with equal gear) creates a very gank box environment in which whoever jumps first, unless there is a massive skill and/or gear disparity, wins. In the majority of fights, I have seen and experienced, whoever engages first wins. It is terrible being ganked with almost no chance of fighting back and winning, and taking death penalties like XP debt and material loss.
Additionally, a lot of the combat's complexity gets made irrelevant with the current short TTK. The game has a 4 attacks basic attack combos that add procs like wounds (anti-heal) and chill that further stack turn into freeze. It has soft and hard CCs like roots and stuns. The fighter has momentum that builds over time. We have damage over time, and debuffs that decrease damage mitigation. None of that matters in fights bigger than 1v1s because players die with 2~3 skills. While you are trying to stack wound debuffs on the target, reducing their armor, and doing proc combos, the enemy is just doing damage and is going to kill you before you can take advantage of any of those mechanics. You don't even have time to properly do 1 basic attack combo to add procs to the enemy, because it is more efficient to just use all your big damage skills and kill the enemy.
A shorter TTK design becomes even shorter when level and gear disparity are introduced. I have actually killed another player with only 4 basic attacks (no abilities used), and it wasn't even a big level difference. I was like 17 and he was 14 I think. The gear difference might have been bigger but even if the guy had all starter gear, he shouldn't have died with a simple 4 basic attack combo. Players starting late and players that don't keep up with the max power players will have a terrible experience if this is the design direction. Players won't be able to participate in content, they will be deleted and killed over and over in guild and node wars, and they have no chance of participating in anything pvp related. And with the current long leveling predicted, how long until new players can start participating in the content? a month? 2 months? can the new player even catch up?
Steven said in a recent interview that: "intrinsically those two philosophies are tied to one another. The shorter TTK and the how do you solve the Zerg problem.". While that is not entirely false, it is not true either. The reason smaller groups have a chance against Zergs on shorter TTK is that smaller groups have a chance to kill a big part of the Zerg by engaging first. But that is also true for the Zergs. If Zergs engage first, they win, regardless of the skill of the smallest group. In short TTK, smaller groups have a better chance against Zergs because of the initiation advantage, and not skill. In fact, short TTK requires less group coordination and skill, as the only thing groups need to do is focus damage (which is incredibly easy since we have marks on the target and target of defensive target key binds).
The good news is that you can also give small groups advantages against big groups with long TTK. The better news is the advantage of small groups over big groups in long TTK actually has to do with skill, team play, and coordination. Having to coordinate the use of all those complex mechanics that you already designed into the game (damage mitigation reduction, anti-healing, CCs, procs, and combos) to effectively eliminate your enemies is a huge advantage for small groups.
In long TTK, a small coordinated group can kill a target in 5~10 seconds, while a big uncoordinated group can kill the same target in a minute. That's a big skill gap, and in the time the Zerg killed one target, the small coordinated group killed 10~20 targets (the same goes for AoE scenarios). In short TTK, a small coordinated group can kill a target in 2 seconds and a big uncoordinated group can kill the same target in what? 5 seconds? the room for improvement is not there.
Longer TTK also gives players the chance to react and fight back against ganks, giving them a better chance of winning and not giving the players that feeling of unfairness in the encounter.
Finally, long TTK means players with power disparity can actually survive long enough to use CCs, apply procs, and participate in damage and healing dealt in PvP content. They won't of course be on parity with geared higher-level players, but they can contribute without being one-shotted.
Please, consider increasing the TTK back to at least the original design of 30s-1min.
TLDR: Long TTK is fairer in games with open-world PvP, more skillful, can make power disparity bearable in pvp, and can help small groups beat larger groups through skill and coordination.