Good point. I am not sure what works better. Don’t think there is ever a perfect solution. Need to compare the options, think about the objectives, do experiments, collect data, crunch the data, find out which solution works better and then implement and educate. I think the people who like to stand on the escalator (and play with their phones) is the majority. People in a hurry are far less (especially when the escalator goes up). But how is the overall flow of the people with and without the stand right/walk left rule, I wonder.
The same kind of problem you have on freeways. Is it better to have strict enforcement of the rule that the left lane is only for over-taking slower cars or is it indeed more desirable to spread the cars, no matter their speed, across all lanes? Again, studies are needed to find out what works better.