I have answers to those who wish to discuss Zwift and Zwift stats. If you are one of those folks who does not like new information and responds emotionally with disregulated hostility please feel free to scroll past.

spelger
What info do I think is 'off' in Zwift?
Answer to specifics: I do not think that data is altered from sensors. Ergo, HR, power and cadence info is not 'doctored.' It is as good as the sensors providing it. However, you ask a great question about how that data is manipulated. Zwift's entire business is predicated on recontextualizing data to provoke emotional responses in users. That's very different from, say, Strava (or more appropriately, TrainerRoad) where the data is presented in a more unbiased way.
What do I mean, specifically?
* People lying about weight
* Adjustability of game settings
* Zwift's poor basic physics engine
* Having massive performance gains as "part of the game" (e.g., you press a feather icon and presto, you have lost 25% of your weight for 60 seconds)

Some of those things are endemic to all indoor training (lying) - but some (the horrendous algebra behind their 'physics' engine; the perfomance enhancers) are specific to Zwift.

mr_pedro - when I can adjust gravity - during a ride - that's not only unrealistic, it tilts any playing field so that it is no longer level.

Note that I have not yet even touched on variances between trainers and trainer types.

The reality is that Zwift is a fun eSports game (if you can get it to work without crashing - not easy for many this week). But it is its own game - not a realistic cycling sim.

What that means for OP is that there are a couple of reasons you might be getting dropped on climbs.
1. Because you told the truth about your weight, and a lot of other riders have lied and cheated. BeCAusE bADgEs!
2. Because you are in worse shape than the other riders.
3. Because Zwift's in-game design doesn't do a good job of translating W/kg to actual climbing speed.
4. Because you are on a decent trainer, and a lot of other riders are on turbo trainers.
5. Your climbing skills are poor.

I know my W/kg on real-world climbs around where I live. I know what I need to put out to climb at a certain speed. And I know, generally, where I am in the pack. It's not replicated on Zwift. And not only that, Zwift does not resemble other online training software (I find this most-telling). Specifically, TrainerRoad and Rouvy both seemed far more accurate to me than Zwift.

Last bit on Zwift for this post: if you doubt that Zwift is an emotional / social product, all you need to do is look at how their user base discuss them. Heated defenses; demoralized hand-wringing when it doesn't work ... and so much more discussion of badges and mY tImE On ALpE d'zWIfT vs. discussion of data and FTP.