While I haven’t flown UA or AA in international business (only domestic F), I do fly DL in both, so quite familiar with D1. My thoughts:
I have yet to see an FA go above and beyond in D1, the few times this has happened it’s been on a domestic F flight. D1 service is fairly consistent, but that’s it. Nothing special.
Re drink refills, I will say I usually find them lacking in D1, I’m guessing it’s due to the volume of pax and the general rush through service. Where they should always be offered when a glass is empty, in D1 they are more likely to pick up your glass and say nothing. In domestic F they tend to ask. It’s gotten to where in D1 I have to be specific and go out of my way to ask for a refill. I used to feel bad about this, being a crew member myself and seeing the crazy folks FAs sometimes deal with, but when one is spending thousands of dollars on a ticket, I no longer think it is unreasonable.
Meal service flow: I have not, since pre-Covid, had a coursed delivery. It’s been all on one tray. Every. Single. Time. Doesn’t matter if it’s international or domestic D1. Day or night. Long or short. I think coursed delivery is the unicorn-like myth of D1. Some folks say they get it always, but other than dessert, I don’t think it exists anymore, despite what the service standard says.
That said, I find the seating of all D1 products to be comfortable, even the 763. I enjoy the lie flat seats and have no problems getting a good rest, which is where I place the value of the ticket most days. While the suites are nice, I do agree some are starting to show their wear. The 763 I was on earlier this week was in better shape than an A339 last year. I have an A359 trip this fall that I’m looking forward to, but will likely be on one of the older/original DL A359s, so mildly concerned the seat will be a disappointment.
Bottomline I think DL is going for the robotic-like consistency of KE in their D1 service and not encouraging above and beyond. Despite my griping, I’m incredibly fortunate and thankful to be able to fly D1, as it’s always on my dime. I’ve done my fair share of coach flights, and the worst day in D1 is better than the best in the back
