I'm in the same boat with you all as well. My thunder breaker originally a second main, but enjoyed the game-play of Thunder breaker for a change of pace that I planned on maining. I've been putting countless hours to upgrade gear to be able to get farther in the game with it. Now it almost feels like I wasted all my time. I'm less concerned about the reduction on damage output as a result, I played thunder breaker because of its unique and fast play-style. I hope Ghiblee's feedback gets reviewed and changes can be made. Sad to say, this latest update has caused me to rethink whether I want to continue playing in general.
The change apparently was intended, but it destroys the fluidity of Thunder Breaker's play style. Comboing Thunderbolt with Tidal Crash is also delayed, and the new update where tidal crash stops makes the class feel even more choppy. Using it mid flash-jump can't be used like before either. The play style was so fast before and the change made feels like the class is ruined in my opinion. I'm hoping they revert back to how it was before the latest patch...