Rankings are a 0-sum game.
You're directly fighting with competitors. If one is doing a better job at SEO then they can beat you in rankings.
Meaning even if you're doing everything right, if they are doing 1% more than you then they'll win.
The best SEO strategy includes work on both ranking improvements and Rich Results. Rich Results aren't impacted by what your competitors do because you quality for them in isolation.
Getting these Rich Results require structured data and the safest and easiest way for Shopify stores is to use JSON-LD for SEO.