I battled the same question 5 years ago and now looking back I’m glad the final discussion was don’t worry about the floor. The floor now has more spills and issues then I can count. My heart would have been fighting to keep the floor clean instead of just working in the shop.
I know I am a bit late to this thread, but the color I choose was Dutch Boy Porch and Floor Tile Red. The paint was put down after all the walls, HVAC, and electrical was completed, no tools etc. The floors were scrubbed with TSP and rinsed several times. It was rolled on. It has been down since 2005. The floor is 5" concrete with a R9 insulation under it. I have attached some pictures, two are of the highest use, the entrance to the shop and entrance to the office. The color does not show up well on the close shots, but the overhead ones give a better color view. There has been no flaking, only places where concrete show through is where I dropped something and it chipped the floor.
Reason for Tile Red is two fold. All my walls and ceilings (10') are white so some contrast was needed for my eyes. Second, a dull red shows up things that are dropped. I do a lot of metal working, so small parts or screws etc can be seen very easily.
After 18 years it is a bit scuffed up but is still fully serviceable, very easy cleanup just wipe up spills oil or otherwise. No different than unpainted, you still have to at least wipe it up or track it allover.