The ACA’s loss ratio rules don’t apply to self-funded plans (many large employers use these) even if they’re administered (and possibly re-insured) by a health insurance company, which is usually the case. Just doesn’t apply at all.

Certain plans also allow much lower loss ratios, like 60/40 for expat plans.

A provider that manages to have a lot of new plans in a given state in a given year is immune from loss ratios rules in that state, for that year. I don’t know how gameable this is but my WAG would be it’s only state insurance commissions preventing this from being the case in every state, every year, for every provider, and keeping it to only some states in some years for some providers (I bet the biggies manage to rotate their state[s] and have at least one most years)

So a company the only business of which is health insurance can easily spend far less than 80 or 85% of income on payouts, and only need maintain that ratio on some subset—possibly small—of the premiums it’s collecting.

I don’t know how the game of this affects decisions for insurers that also own providers, but I bet there’s something beneficial there and that’s why they’ve been snapping up provider offices for the last several years.