PhysioTrueUP not working and gone?

This many of us bought it on the fact it was there for the reviews and feature we wanted and now have the bait and switch. 

Look if I was just going to discard the ride on the head unit I would of got a cheap unit for the radar and stats at a glance, I wanted to be able to not have to use the watch each ride, they could have at least added screen share like the 130 has if they made not recording the ride in the Expore 2 worth it.

I recently got a Fenix 7s Pro watch and went for my first ride yesterday. It certainly feels dumb having to launch the activity on both (so that I can follow the course on my EE2 and see my data fields) only to discard the recording from the Edge and keep the one from my watch. That's just excessive.

However, the watch brings many performance metrics that the EE2 doesn't have, e.g Training Effect and Training Status. So even if Physio TrueUp was available, you would still lose this valuable information by using only the EE2 to record the activity.
I tend to think that the fact the EE2 has about the least amount of performance metrics of all Garmin's fitness watches / cycling computers is maybe the reason why it cannot sync with other garmin devices. It wouldn't make a ton of sense to record the activity on the EE2 if you have a Fenix that supports a lot more performance metrics, even if you could sync up activity minutes etc.

The "problem" remains nonetheless. I'm using quote marks as this is of course a prime example of an ironic "first world problem".
Personally I'm considering selling the EE2 and getting a secondhand Edge 840 instead.

That is what true up does, it takes the edge ride without the TE and TS and uses the watch to calculate it. If true up was still there you could record on the edge explore 2 and have all the data of the fenix 7 which is why its upsetting it was removed 

I am not sure about that, but maybe I'm wrong... My understanding from reading the support page for Physio TrueUp is that it just shares existing data between devices. So for instance, EE2 supports intensity minutes, heat acclimatation, recovery time, but doesn't support training effect nor training status. So the data that is supported by the device would be shared to other devices that also support it, so that e.g my recovery time / heat acclimation on my watch gets updated if I record an activity from my Edge. But from my understanding it would not add a training effect to the activity recorded on my EE2. At least I can't find anything in the support pages that supports this idea.

It's a bit tricky since the support page for US doesn't say exactly the same thing as other countries. But for instance on the US support page it clearly says: 
"NOTE: Physio TrueUp will not sync data to a watch that does not have that specific feature."

But honestly it's pretty hard to understand from the support page alone, so I'm not 100% sure. I'm also struggling to understand the difference with Unified Training Status. Although it does say that syncing training status and training readiness between devices requires Unified Training Status anyway...

All that being sad, the funny thing is that a lot of my Fenix data has made its way back to my Edge Explore 2. For instance, activity minutes on my EE2 are up to date with my watch, as well as heat acclimation, physical age and recovery time. It even added my Stand Up Paddle activity (recorded on my watch) from today to my Edge. However it thinks it's cycling activity instead of SUP and has even populated cadence data, using the paddle stroke rate. Now It makes me wonder if it would work the other way around (from the EE2 to the watch).

This is what a Garmin customer support agent write to me a while ago:

"The benefit of recording it on your 965 would be that the watch and Garmin Connect would line up Training Status-wise. You used to be able to toggle between different device's Training Status's, but that's no longer the case. The goal of that change was to make your Training/fitness data more seamless and unified. If you record an activity on the Edge, the Training Status that shows on the Edge won't be the same as what is displayed in Garmin Connect."

So they admittedly removed some features that were there at the beginning. While here TrueUp isn't mentioned, as far as I understand (from the context of the other parts of the email) that is the feature they removed.