Maybe not yet but if people's circumstances change post Covid-19 e.g. two car household going down to a single car due to reduced income there could well be a decision to use rail more.
Indeed, also if there's an increase in working from home this could also reduce the number of cars.
As an example if there's a couple who both work from home two days a week then there'll only be one day a week (most weeks) where a second car would be needed to get to and from work. As such the justification for a second car would be harder to make.
For instance if currently each person pays £50 a week in fuel driving 5 days a week (£100 total), if this changes to one car with one person using public transport to get to work on the days where they both need to be in the office this could change to £50 for fuel and £15 in public transport costs (£65 total) or £30 each in fuel costs (£60 total). Now whilst the cost of using public transport would appear to be higher the upfront costs aren't included in the above and so are likely to be a lot more than the £260 which the above would require.
As such there would be some for whom a second car wouldn't be justified.
As I've highlighted before, given that 80% of travel is done by car, even small numbers changing would be able to offset reductions in rail use due to working from home, as rail is only 10% of travel.
However that's just the impact on working, without two cars there'll be some leisure travel which would then need to be undertaken by public transport as well.
There's also the fact that the longer this goes on the more accustomed to getting things delivered and so won't be so inclined to using physical shops. With people working from home they are more likely to be home to receive the delivery, which is often cited as a reason as to why people don't like ordering things.
Even parents with a stay at home adult who need a car for certain clubs/after school activities could have the working parent working from home on the days of those clubs/activities, so as to remove the need for a second car.
The more changes that there are, even if this unfortunately results in some people having lost their jobs, the more likely it will be that there'll be changes to the way we travel. Whilst that's going to change every mode of travel the modes which are most likely to see the biggest losses are air travel and car usage.
Things like cycling and walking are likely to see an uplift, especially given that people will have got used to doing so with quiet roads, so will know what life with a reduction in cars could be quite nice and so may be more inclined to try and keep it that way.
A 10% drop in car usage would make the roads feel like the school holidays all the time, where there's hardly any congestion in many areas (tourist areas obviously see an increase and so often see more congestion).