I'm not seeing it.

The problem is not skill speed. The core issue you're aiming at is the softcapped TP resource pool. This results in a game design issue where encounters are constrained and high-end content will have only 1 design approach: high-intensity / short-duration fights with low AOE components. It makes it very difficult to design encounters with long-duration strategic mechanics.

Skill speed itself only has two issues: (1) its exponential scaling at all, and (2) the fact that SS's value is softcapped by animations. The secondary issue as a result of those is that the raw magnitude of skill speed is slightly weak in light of #1 and #2 above.

However, the SS issues can be lived with: it has a softcap? Don't stack it. Solved. What actually negatively impacts the game as a whole is the TP resource design. In the end, you're using the general sentiment re: SS as an segue to the real issue. Just cut out the middle man.