WTH datetime picker is so clunky?

Hello
While there are several WTH about things related to date-time picker, I found no so far about its limited usability.

Let’s go straight:

  1. arbitrary 5-min resolution is not enough. How to select range from within this range? ie 10:12-10:14 ?
  2. inability to enter date/time manually (see Grafana for example)
  3. Inability to use calculated values (again, like in grafana)
  4. no copy-paste between date-time pickers
  5. predefined time ranges are covered by another, already existing WTH

I assume that part of the reason is to make this picker mobile-device-compatible—especially this 5-min selector looks like a compromise made 10 years ago because of that.
But today there are better selectors available (ie a barrel with rolling numbers.