Oh, they don't need a reason to let the core product stagnate. They've been doing that for years.
I only use their DataGrip product. Compared to the competition they are iterating at lightspeed.
That's unfair. They released plenty of fresh performance regressions
The war in Ukraine and subsequent move to Czechia did seem to hurt them pretty badly, but I wouldn't say they are stagnant. I've been a happy customer of PHPStorm for years and it continues to improve.