I used an iPhone via T-Mobile on 4G (I have 5G deliberately disabled, maybe that could help) in chat the other day. Not a single disconnect. Not a hiccup.
There's no recommended settings and I'm not telling you to talk to devs. Don't misrepresent what I stated. Thanks.
Just like with any website or software, given potentially unique circumstances, your mileage may vary.
You said to “talk to their developers” about the issue, and then said “Developers won't discuss those things with you in-detail.” There is no misrepresentation here.
I will just have to accept the fact that you’re unable to help me with this issue. Thanks for trying.