Headstart player here. Just thought about jumping in and giving my 2¢.
See, the game went through so much over the last decade that the things that the playerbase is receiving are quite huge. We started off with an unclear direction (gear, economy, LFG tools, progression, etc), at least for an MMORPG such as GW2. Dang, when HoT was teased countless rumors were flying about what that thing could be, because we almost had no spare hope left for what this game could evolve into. I remember I screamed when they announced it was, in fact, an expansion!
But wait, GW2 would never ever have one expansion, just regular story releases and whatnot. Guess the market prices itself and it's ruthless, but then again what would we be doing in a stale game after all? Then they've challenged their fixed mindset about the holy trinity: it will never happen. But it did! Well, sort of, the trinity flows more dynamically than normal and it's broken into multiple pieces. Piece by piece, things started changing for good, amongst so many heated discussions and curious developments company-wise. The amount of time we gave this game into repeating gold grinding in the past is far beyond comprehension, it's not even close to what we have now.
This game is and will remain a B2P model because of how it started and the big players behind it. That won't however hinder their abilities to grow and make money, but that's topic for another time.
Specializations, a.k.a traits, balancing happens quite normally for a F2P model game cadence to be completely honest. The feedback is important, but they will milk money from unbalanced classes and tbh that's another thing that should be expected. One thing should be expected (and this is targetted at the devs) is world polish. It's unreasonable to have quite a few annoying, long-standing bugs tied to graphics. This is why one of my main complaints since roughly 6 years ago was to upgrade DirectX. It takes a lot of resources, money and research, but whatever, everything has only one direction: forward. Or downward... the choice lies at the hands of the big players mentioned before.
About the game getting worse: that's the price you pay for denying the chance for a product to grow for way too long. You can't stop the flow of the game + fixing the already existing bugs. That's a painful cycle that you must endure and overcome, there's no magical way to get everything beautifully in place.
Game has potential, just like it did 10 years ago. You really have to put on the work and that's about it.