It seems like getting anything under 20 seconds is extremely unlikely, if even possible at all.

The best way to get a good time requires extreme reaction speeds and a bit of luck to predict which pill is going to come up as well as when you will be able to launch that pill.

One way to do this would be to keep retrying over and over again until you get 4 of the same colored pill for all three types of pills in a row, (example, 4 reds in a row followed by 4 yellows in a row, which then opens up for the 4 blues in a row), as it completely removes the need to process which color it is before launching.

I personally have had runs where this had happened but I never trusted the RNG to actually give me four in a row. My 21 second run was a 1 miss run.