Deactivating slow effects (Full Reverb) still slows down response time.

I actually already found a solution to this problem: Pre-Rendering effects track. The lightning bolt icon in the effects rack.

However, I found it odd that despite deactivating the Full Reverb Effect in the effects rack, hiting play or going back and forth in the timeline of a session would have a 2 second lag.
Soloing a track that has no effects also had a slow response time.
Only deleting the effect made it respond imediately.

Shoudln't deactivating the effect treat the track as if there was no effect?