Article thesis is that funds go around that limit. Not even on purpose, just by their definition. No single company has monopoly but index funds collectively own all of them.
The article also explains that this is only true when a few large players control the market. E.g. an index that includes all of the major pharmaceutical companies. Indexes generally don't invest in startups taking on the incumbents, so there's an opportunity there as long as competition is realistic / the existing players are not too entrenched.
Article thesis is that funds go around that limit. Not even on purpose, just by their definition. No single company has monopoly but index funds collectively own all of them.