Maybe it's just because I'm fat and slow, but there are a lot of folks using zpower in the lower cats (they don't show up in the results on Zwift Power after they rode away from the field on a dumb trainer using the wrong settings or with their wheel not cranked down tight, but I'm afraid that will change). Not at all calibrated and putting out insane watts (for us at least, maybe reasonable for A+).
Zwift has previously shown that they don't care about people using zpower in races and, other than their cone of shame in a few races, don't really seem to care about sandbaggers either, they just say, "if you want your results, check Zwift Power". They just want as many subscriptions as possible.
Now that Zwift is running Zwift Power, I'm afraid they'll stop requiring actual power and heart rate readings to show up in the results and it will kill any rational competition.
Maybe they won't do that. Maybe they'll be super cool about it and integrate Zwift Power into their site and make opt-in to Zwift Power results automatic so we can see everyone (other than zpower users and those without heartrate monitors) in the results. That'd actually be cool. I don't care if it drops me down in the results as long as the results seem real. Maybe they'll use the Zwift Power average of 95% of best 20 minute power over the last 5 races to determine minimum cat and make hard floors to eliminate sandbaggers.