Saying 1 final, 1 semi-final for the same tournament is counting the same thing twice, right? We say Astralis Top5/Top6 at IEM Katowice 2021. Do we say Astralis Top24, Top23, Top22,......., Top5/Top6? It's a common sense logic.
Niko had 1 major run where he made it to the finals. That's it. s1mple had 5 major runs. In 3 of them he made it upto semis and got knocked out. In the other 2, he made it to the finals. I will count each tournament only once, like a sane person.
However, if you want double counting, here you go:
s1mple - 2 major finals, 5 major semi-finals
Niko - 1 major finals, 1 major semi-finals.