You’re saying it’s impossible to have an optionally required feature? If the satellite TV is down some sensor data isn’t sent. Why would that be cause for grounding the plane? You could easily make the regulation an SLA like all routes flown must be sending data for 90% of the flights on that route for the month and failures to meet the SLA are investigated.

Also I’ve flown a bunch and I’ve rarely seen the Internet link go out except where there’s technical limitations like crossing the ocean where they can’t maintain an internet and have to rely on preprogrammed content. Given how much money they make from cabin internet, the airlines are clearly incentivized to apply pressure to keep those things running. I doubt I’ve seen anyone be really annoyed when there’s technical difficulties. Most people who fall into that category would have made other arrangements for entertainment anyway.