That is right, but your machine can’t go from zero to 30 instantly. It can try, but it would be likely to skip steps and generally not be terribly reliable. The firmware limits the max speed and acceleration. So, 30mm/s would be closer to traveling 300mm in 10 seconds than 30mm in one second.
The diameter should be the maximum diameter of the v bit. You’ve got it set to 0.1mm, so it’s probably driving over the same area over and over, moving 0.1mm per pass.
Update: re-worked my tools and spent a significant amount of time understanding the various setting in Estlcam which seemed to resolve my issues… Thanks again Jeffeb3 for the clue.