Cheating means your whole journey from nobody to pro player was illegitimate.

No it absolutely doesn't. A good amount of current pros previously cheated, both in CSGO and previous iterations of CS, and many more did but haven't admitted to it. n0thing has said he has cheated in the past, along with Shroud and others. It's a dirty secret, but in 1.6 turning on r_drawothermodels 2 for like half a second was a common thing to do when sv_cheats wasn't always protected in online league matches or in sketchy tournaments. Also the no smoke method where you made a copy of the sprite in the installation folder and deleted the original to be able to see through smokes. A big, big chunk of current pros that played 1.6 cheated at the game occasionally, and in the modern context it was just the growing pains of an e-sport, and today cheating is far far harder to get away with.