To attempt to inform this discussion at least a little, I can add the following passenger numbers analysis from passenger flows in London and its surrounds.
This is how passenger numbers are spread across the week compared to the average for weekdays (Mondays to Fridays) based on Autumn 2022 data:
Mondays 89% of the average weekday
Tuesdays to Thursdays 104.4%
Fridays 97.7%
Saturdays 87.2%
Sundays 59.5%
I also looked at how much demand occurs at Peaks times on weekdays, so closest to what Mark Harper presumably regards as 'typical office' commuting, although clearly some commuting occurs across the whole day every day of the week. Across the week, 47.7% of all station entries and exits are at 'peak' times (between 0700 and 1000 and between 1600 and 1900).
On Mondays this number was 50.4%
The average for Tuesdays to Thursdays is 48.8%
On Fridays it is only 38.6%
This clearly shows that the weekday peaks are still by some margin the busiest times of any day, even if they have not recovered to quite the same degree. Mondays and Saturdays now have quite similar passenger numbers overall now, but on Mondays half of these are at peak times (44.6% of those in the AM Peak), whereas on Saturdays only 33.6% of the journeys are at times that would be considered 'peak' on weekdays (and only 30% of these are in what would be the 'AM Peak).
Total demand during Autumn 2022 was 79.3% of that during Autumn 2019. This puts us back at 2010 demand levels, that is the current passenger numbers are the same as they were in 2010 overall. The period 2005 to 2013 saw very strong growth (traffic had been growing slowly since the early 1990s up to that point and continued to grow, but more slowly after 2013 up to the start of the pandemic. The trend through 2022 was one of steady recovery throughout.
Interestingly a piece of work I did in 2017 (though limited to one route using 2016 data) found that passenger numbers during Friday peak times were only 89% of the average for peak times across the week, suggesting even then that Working From Home was becoming an option for some office workers...