The pre-race data dump from the TT ZERO Clerk of the Course also includes the "Fastest Laps" list, in addition to the starting positions for the race. The information on this list just makes me more confused about how the starting positions are decided:
In any case we see in this data that there are two separate races. The top three bikes, MotoCzysz and Mugen Shinden, are showing speeds much faster than the rest of the pack.
This is similar to what I was observing last year in the TTXGP. Not every team can afford to build a top of the line electric superbike. That meant the TTXGP ended up with a few ultra fast bikes, and a larger pack of bikes that aren't so fast.