It’s not the Karen’s directly that are causing these games to struggle, it’s that for every hardcore PvP vet and fan you have, there are 100,000 Karen’s that are also whales, ready to drop thousands of dollars on cosmetics and extra energy to win the game by buying their way through it. I don't think people realize that games like Minecraft, Fortnite and the Sims 4 make more money alone than the combined total of all other games released over the last 5 decades. There would be 100,000 times more people playing MO 2 today if they could tap into .1% of this market and it wouldn't take very many concessions to do so because even these players are looking for more challenging gameplay, just not quite as hardcore as most vets want MO 2 to be.
These markets are available and can be tapped into by games like MO 2 because there is a very large portion of these communities that have grown very unsatisfied with the low level and depth of modern games. They want challenges a keen to MO 2. We saw a lot of this even in MO 1 where players coming to the game from the likes of World Of Warcraft for example looking for something more robust and interactive.
Open-world, full loot PvP’s simply don’t represent a community large enough to sustain an mmo (any MMO) on the really hardcore level, some concessions must be made. Eve Online is a great example of these types of concessions working, it's one of the few deep MMO's still profitably operating from the early 2000's. This has been the reality for decades, people keep trying but ultimately games are businesses and people need to make money which leads them to compromise these designs to attract these other markets where even if you can just get a tiny snippet, like 1%, MO 2 can sustain.
The reality is if the hardcore PvP vets get the game they want, its failure is a 100% certainty and there is 40 years of data proving that beyond the shadow of a doubt and 0 data suggesting there is a route to success.
In a sense, MO 2 must compromise to succeed and the details of that compromise will determine how many vets remain. The reality is that they really aren't needed, with the right compromises, MO 2 will tap into a wider market and like Eve Online, can continue for a couple of decades with vets bitching about it, while the game succeeds despite them.
The devil however is in the details and the thing I worry is that it will compromise itself in a way that excludes Vets yet not sufficiently to attract a wider market. This was the problem with MO 1 and Darkfall for example. A lot of it however was more marketing then reality. MO 1 for example had a reputation due to the marketing for being a super hardcore PvP game and so people never even tried it. It was a terrible marketing strategy. If you look at games like Eve Online, they pitch the expansive world, the cool niche features and the high and low levels of gameplay. MO 2 needs to be more gracious and inviting to people who want to play casual, solo etc... if it wants to capture these markets.