This is travel rationning which is very much needed as a response to the Climate Change emergency. I doubt anyone has even given this the serious thought it needs. I would expect something rather more significant than a 20% cut in travel (not just the railway) is needed.Absolutely, totally and completely not. Travel must be reduced; that's important to reduce our carbon emissions starkly as will be necessary.
There is enough car travel going on to keep the railway going for as long as it wants without deliberately creating new travel.
How well are we doing with making working from home carbon free? At the moment, it isn't great - eg more heating over the winter and the cost of data centres to provide the internet.