I'd say the Supercharger network is a big advantage, but the difference in efficiency (energy used for you pedants) as well. The range and performance plus charging cost due to said efficiency is quite different between the Model Y and e-tron. Heck, even the Model X is more efficient than the e-tron and it's significantly larger.
And not sure I agree on better UI on the e-tron. That's certainly a matter of opinion. The 15" touchscreen used by Tesla is exceptional for navigation and general ease of use. But the interiors and overall vehicles are quite different, they'll each have their buyers.
I've never gotten anywhere close to the rated range on either the Model S or the Model 3 in any real world driving. Now sure I can get there on a summer day if I drive slow.
Sure I can get there by using the smaller uglier tires/wheels. But, for all practical purposes the rated range is meaningless to me. So on that one I'm going to wait to see what people actually experience. The Germans tend to be more conservative with numbers they give than Tesla tends to be.
Now I don't expect it to be as efficient since nothing about the E-tron screams efficiency. Instead it looks to be a vehicle designed to trade off efficiency in favor of more durability, and a more richer interior. I imagine it's quieter inside than either the Model Y, or the X.
I keep going back to the charging network because it's the one thing Tesla did so well on that it's hard for anyone else to compete. It's not just how they did the supercharging network with how many stalls (on average) a site has, but it's also the destination chargers as well. It's so well done that I don't even need to stop at a supercharger on my trips to Portland. If I drive conservatively I can do the almost 200 miles trip without stopping to charge. I simply book a hotel that has destination charging.
I preferred the UI of the S because I could have all the information I wanted displayed where I wanted it. I really felt at home in that vehicle and part of me is kinda bummed I traded it in.
The UI in the 3/Y is clearly designed with autonomous driving in mind. That would be fine if we had autonomous driving, but instead Tesla is taking an iterative approach to autonomous driving.
The iterative approach means that the UI/UX of the vehicle needs to be aware of what the driver is doing (are they paying attention), and it needs to notify the driver to what it detects.
As it is right now drivers like myself miss half the notifications the car tells us. It's off to the side, and I'm paying attention to the road. I really wish Tesla would add a notification history. I'd also like them to add the notifications to to the dashcam video (like a closed captioning that could be turned on/off).
We also struggle with torque sensor failing to detect our hands properly. Even if it did work better it still would be in inadequate way to measure driver engagement.
I think it's too early to tell what the Model Y will have. Over the next year or so I expect Tesla/Elon to transition away from the torque sensor to a system similar to what the Cadillac Supercruise system uses.