Somewhat surprised at the comments about XC being decent. I've just come back from up North after a weekend away and the WiFi was basically unusable for most of the Bristol - York stretch and back again. I had much better luck on mobile data (which says a lot given how rubbish signal can be on that route, even more so once you add in the effects the Voyagers have on phone signal). Maybe others just have lower expectations than I do, but I would expect a modern internet connection of any type to be able to deal with refreshing a Twitter feed properly! Granted both journeys were very busy (the TM declassified first class for a period due to how busy the return journey was) so maybe my experience isn't reflective of the usual experience when less people are using it (certainly when it used to be paid for it was actually quite usable IIRC).
The fact that both journeys were busy would've had an effect on the usability of the WiFi, plus if some people start using high data services it could have a knock on for the rest of train.
When you had to pay on XC for WiFi, i'd sit in standard and use the toilet in 1st for a moment if i was that desperate to connect online. I think WiFi became free to standard class late 2018/early 2019, so didn't use the tactic since.
I've often found it reliable on XC irrespective of rolling stock, which is nice compared to the differences on GWR, where the 16x and 9 car 80x units may as well not have it (the 16x stuggle with loading the Google home page, 9 car 80x is a mess to even connect to). The 15x and 5 car 80x units fine, the HST fleet doesn't like RTT at all but is fine otherwise, and the Night Riviera isn't great (but as it's a sleeper and i tend not to sleep travelling it gets a bye).
