Insurance in the small group market isn't subsidized; it's employer-provided. So subsidies can't be confounding those statistics, can they?†
I'm not disputing that you experienced a barely-tenable increase in insurance premiums since 2011. But if your premiums had been increasing 30% YOY since Obamacare went into effect, you'd be paying something closer to $5000/mo, not $2200/mo. What you experienced instead looks closer to 13% YOY.
The distinction is important because:
* The California small-group market, which like most group markets was guaranteed-issue prior to ACA, was already experiencing increases at that scale before ACA.
* Not only was that happening, but further cost increases were easily hidden by terms and conditions that reduced actuarial value for policies at the same premium. The ACA prohibits that practice; if the broader narrative about ACA was true, you'd expect even steeper price increases because insurers have fewer ways of hiding them. But we don't see that.
So to me, you're telling a story about broad dysfunction in the health care marketplace that is orthogonal to ACA. I find that narrative very easy to believe! Either way, though: I might be wrong (and would love to hear about it if I am), but these issues aren't unknowable.
† This is one of several reasons you know you're in trouble when you read an analysis of the ACA that insists on comparing the pre-ACA and post-ACA individual markets, or suggests that comparisons based on the small group market is somehow shenanigans: in addition to being the insurance market most of us startup founders actually participate in, the small group market is the closest we have to an apples/apples comparison: an unsubsidized guaranteed-issue marketplace for small numbers of people in both eras.