2.5 hours is a bit too long, 1.5 or possibly 2 hours would have been better as long as the route was served by a TGV.
Japan has an excellent high speed rail system and could easily do the same, with very little disruption.
In the UK, from London, rail travel predominates as far as Newcastle. North from there, even though the extra distance to Scottish cities isn’t great air travel takes over. Train to Newcastle, fly to Glasgow.
A similar ban wouldn’t be possible in the USA due to the lack of a decent rail network, let alone a high speed one.