Isn’t this already here? ~5 years ago I remember watching Netflix, playing rocket league and remotely accessing as unix server during a flight.
For international longer-haul flights satellite coverage can be rough for airlines - at least a few years ago when I was familiar with it airlines had either global coverage, but slow, or smaller coverage but fast.
It'll be interesting if Starlink can solve this for fast-moving planes for airlines like Qantas that fly from Aus to Europe, Asia, and America.
It's different for every airline, but I believe the system for Southwest just uses signals from cell towers, which is spotty at best.
Most of the major US airlines have been migrating from cellular to Ka- or Ku-band satellite internet over the last few years. (Including Southwest.)
There's some individual aircraft that haven't been upgraded yet, since installing the satellite antenna is a major upgrade. But at least on my flights, most offer it now.
Maybe depends on what kind of tech is installed on plane, but there is definitely space to improve it.