You can try, but:
Imho (just my2c, I fly always with internet on the device) is that not a problem, not for high performing phones, at least!
I fly often with my "main phone", which is then connected to mobil data.
Or with a tablet, which then has a wifi connection to my main device.
The problem, that mobil data, or a wifi connection, can get you in:
During flight some messages are popping up or a phone call comes in, stuff like that.
You get easily distracted? flightmode
You can swipe it away? never mind
As long the remote is connected via cable to the device, I really don't see there trouble coming up.
But what I think can be, with your new 5G phone:
It might need a different app to work well.
So the next one, perhaps.
Or try an older one from last year, just for a test