[cperciva]

Actually "old systems" aren't the bottleneck.

It's limited gates and radio frequency time.

Did we read the same article? One of the problems specifically mentioned about old ATC systems is that they rely on voice communication while text messages would be more efficient.

[Aloha]

I see obvious safety issues with relying on text messages for aircraft communications, notably situational awareness.

[Karrot_Kream]

Have a digital frequency for routine communication: like authorization to taxi, take off, clearances, flight plans, pattern requests, confirmations, and traffic. Keep an analog frequency for communicating through emergencies (kind of like Guard).

[bencoder]

Sometimes dangerous situations are averted by pilots realising the controller had made an error, like clearing a plane to cross a runway while another is taking off [0]

This kind of thing might be much harder to catch if clearances are given in text, or even impossible if they are routed only to the specific aircraft.

[0] https://youtu.be/w9lXcDYTg3Q

[TheSoftwareGuy]

You could maybe have a speech synthesizer on the other end?