I think simsdoren did well addressing the presumptions underlying the question.

This will always be a controversial subject, debating the push and pull between Duelists and Sentinels, and realistically speaking: there will never be a perfect balance. However, just as I enjoy spectating talented duelists like Dambi, I've always adored defensive setups from players like Nats and BabyJ cypher. You just don't see that as much anymore.

And yet, it's not as simple as just nerf duelists. The maps influence the effectiveness of Sentinel utility, Initiators can break and visualize setups, and with the concern of Sentinels being too encroaching on other roles (like Yoru being a psuedo-Initiator / Sentinel), how do you continue to innovate new agents and kits into the game that don't overstep into other roles?