I still like using HSS for general purpose small hole drilling. This is because HSS is tougher than carbide, and can stand a bit of incidental shock loading. But for larger holes, carbide insert drills are really nice, if your machine has the horsepower to run them at their design speed and feed rates. When you run out of horsepower, then you are back to HSS and spade drills.
Part of what is taken into consideration in a small shop is the ease of resharpening, drill bits especially. To sharpen a carbide drill properly requires expert technique to regrind the point properly. HSS is more forgiving, and grinds easier by hand on typical tool room grinding wheels.
For milling, HSS used to have quite an advantage pricewise. On a manual machine, HSS is still likely the best choice for small endmilling, due to inadequate coolant, spindle hp or feedrate capability of the machine power feeds (if present). Carbide insert facemills do work well on manual machines.
Carbide works very well with smooth controlled entry into the cut, with high, steady feedrate in proportion to spindle rpm. Without those factors being at their best, the carbide is likely to fail prematurely due to chip recutting, built up edge, and of course, the tendency to workharden the material is greater because of the greater speed capability of carbide, if the tool dwells on the part while the operator struggles to control what is going on.
First you get good, then you get fast. Then grouchiness sets in.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)