I can see long term a reduction in peak hour commuting and increase in off peak commuting as people work partly from home and go direct to and from meetings etc.
My guess is that home counties commuting will be hit far more than inner city commuting or inter city commuting for three reasons.
Home counties commuters more likely to be doing jobs that can be done at home. Fares are high so big incentive, and thirdly a slew of home counties commuters will move further out, as if only going in occasionally, can tolerate a longer commute when they do go in and get a much nicer house for the money.
This third one will be boosted also by HS2.
I don't think it has gone unnoticed either that with the reduced number of trains, things ran more smoothly.
The other vibe I get from the Telegraph article is that funding is at the root of it so you could see traincrew etc stood down/furloughed or whatever the equivalent is this time. For train drivers in particular furlough would bring a pay cut of ~60% due to the cap on the furlough pay of roughly 80% of £30k.
Also wonder if Bustitution will be deployed bearing in mind the above.