Most measurements of large current don’t need the extreme accuracy of microscopic electron counting, but there are some really important reasons why it is a neat technology.
As far as we know, all the electrons on earth and in the universe are exactly the same. This makes electron-counting a route to a standard that is truly 'universal'. It doesn’t matter exactly which electrons you count or where, or when. This robustness and universality is particularly valuable on the frontiers of science and technology, where other things are unknown.
Scientists are often trying to discover new things, improve people’s health, protect the planet and other lofty goals. This often means measuring and interpreting sensor signals. Sometimes these signals are really tiny and difficult to measure accurately - environmental sensors are often like this. Standards for small electrical current measurement, including electron counting, will help make this sensor data meaningful.
In fact, since the redefinition of the electrical units in 2019, all measurements of electricity are ultimately related to numbers of electrons even when they are not being counted one at a time.