TBH, you are partially right, about no one having a clear advantage in CS, being entirely skill based etc.
What you kinda got wrong imo is everyone having a set role in Valorant... Like, it's far from it... For example, if you play Sage alone on site that's being rushed by a whole team, you would quickly need to retreat and play retake as in that case, even Sage's defensive potential becomes obsolete. You are required to use agents differently from their surface-level intended use in order to carry out rounds properly. Now you would need to place Sage walls and slow orbs in other places, using them differently than intended in the beginning of the round to play retake by closing out the angles, or, try to lurk with an agent that possibly doesn't have best utility to carry out his given task...
That kind of more than necessary adaptation exists in CS too, of course, but with so many agents & with so much utility being played, plus, metas changing and being innovated all the time, learning curve becomes even steeper than CS's if you ask me... And even after all that, and utility carrying out the final kills in the round, the game still comes down to landing your shots.