M390/20CV/204p is definitely not a "tough" steel from everything I've read. I don't use my knives super hard often, but if I do, I choose something that has better edge stability, like CPM-3V or CPM-M4, or even CTS-XHP.
Also note, Spyderco tends to make thin, slicy blades, which also affects edge stability.
I've also found many other companies tend to run M390 etc on the soft side, possibly for this reason. The best examples as far as edge retention (and therefore correct heat treat) have been 204p from Spyderco (Southard) and Cheburkov M390.
It comes down to the right tool for the job, which means the right steel and edge geometry.