The post manage to analyse terminal input without having acknowledging readline. So yeah, they have no idea what they are talking about.
https://www.masteringemacs.org/article/keyboard-shortcuts-ev...
They could write an "interactive shell" with mouse support that implements all those features and it would run in any pre existing terminal. They could even make this work with existing shells and it would work over ssh ect. Nothing against innovation but this is the wrong approach imo.
They're not writing a technical deep dive, they're presenting their vision for a different approach. I think that vision is flawed but I'm not going to grade them on how deep they get into implementation details.