I changed the display settings between energy and distance but it didn't seem to change anything in the graphs themselves.
Yeah that was just so I could extrapolate your miles at 100% for this particular capture, for consistency with your prior screenshots. Looks like 259 at 78.7% or so, so about 330 (you saw 331 so that seems the same as one would expect - I'm pretty sure the answer is 331, and it's not working out to exactly that, because of some rounding errors or oddity in how Tesla displays the SOC on that Trip screen - maybe SoC is actually 78.5% for example).
Anyway:
336Wh/mi*185mi /0.787 = 79.0kWh (This is the approximate degradation threshold.)
So this energy screen has a higher degradation threshold than previously (AFAIK it was about 77.8kWh before, but I'm not certain of that as I'm not following Model Y closely - I just think it was the same as Model 3 until recently).
It looks to me like Tesla is treating this new Y as a 331-mile range vehicle rather than a 326-mile one, for now.
Note 79.0kWh/331rmi = 238.7Wh/rmi which is about the same constant I mentioned above. That's what you expect from the energy screen - it seems to always work out to the same value, until Tesla changes it.
This method gives you the MINIMUM energy your vehicle has. It's possible (likely) that your vehicle currently has more than 79.0kWh (it nearly certainly has the 82.1kWh battery after all - though typically those have been showing energy closer to 80kWh, not the design capacity "Full Pack When New" value of 82.1kWh).
So as explained above, whatever your current energy (you'd have to have SMT to know), you're not going to see
displayed range loss on this vehicle until your capacity drops below about 78.9kWh (the apparent degradation threshold, less half a rated mile of energy). Prior to that time, the energy in each rated mile is just a bit higher than 239Wh; it just increases to "fit" the energy into 331 such units. So, it's possible that you have a pack that actually has 81kWh (though I think unlikely) - but you'd still see 331 rated miles, with each mile containing 245Wh.
Other people with Model Y LR showing less than 331 miles at a full charge have somewhat less than 79.0kWh pack capacity. All the LR Model Y look like they have the same constant (though I can't speak to the prior model year, as it depends on what Tesla did with the software update - I think they aligned them all, but I don't remember).
At least, this is my understanding of how it works. If we find information that suggests differently, I'll change my framework to fit it.