Comping. Removing all muted takes in a track

Tried it and found what you're asking about: the clips get deleted but the take lanes remain (empty).
I did find it was fast to delete each lane with the little 'X' button on the bottom left if that helps (so you don't have to select each track and delete, just click the button, it deletes the track and the next one below it pops into the same space so its 'X' is under the cursor for another click and delete.

I think if you bounce everything all the muted tracks go away automatically.