ArenaNet is launching Guild Wars 2 beta testing for DirectX 11 integration today and while it's a great step forward, it's a good idea to temper your expectations.
Guild Wars 2 DX11 beta is starting on September 21, 2021, and it's got countless fans hyped up all the way to the moon. However, many are undoubtedly going to be disappointed and not through the fault of ArenaNet.
Low FPS is certainly one of the biggest issues GW2 has had ever since the release nine years ago and DirectX 11 will definitely help here but expecting a miracle after it comes around will only lead to disappointment.
First and foremost, this is the beta testing phase of the system, not a full release. As such, it's fair to expect that it's not entirely complete and it's the players' feedback that the devs will rely on in order to improve it and eventually deliver a better experience.
Another thing to keep in mind is that the engine still has its limitations and while DX11 will result in FPS boost for some players, not everyone will see the same increase. This will depend on your rig so it might end up being only a few frames of difference and maybe none at all.
For those that do get improved frame rates, do not expect a massive bump, especially in the worst scenarios like WvW zergs or an open-world boss. Everyone is aware this is the part that interests players the most and while multithreading will help, it's just not right to expect 120 FPS when the game has to render 120 players beside you.