Not true at all.
A great example was this market from the most recent primary election.
https://kalshi.com/markets/kxtxsenatedemturnout/voter-turnou...
Based on just simple math there was basically no chance of turnout being over 2.5m and yet the market for multiple days had the higher buckets at exorbitant prices.
The turnaround was 2.3m, I don't get your point. Texas doesn't require party affiliation.