It's a difference in how the question is phrased. Most people do essentially no research and make no effort to understand the details of things. In this case it's choice = good. No further thought is required as to the actual value added by private insurance.
Defending America’s status quo by saying “choice = good” is one of the crazier things that comes up in these discussions.
A person on Original Medicare today has much more choice because there is no “in network”. All physicians[0] and hospitals and clinics are accessible, without restriction. Also, countries with national care systems like Canada and the UK still have supplemental insurance markets, if you really want that extra choice—but they are small because most people are satisfied with the state-funded care.
The main “choice” you get with the private insurance system these days is which company you want to be locked into using for the rest of your life, as they seem to be increasingly dividing the market so that doctors from health care system A only accept insurance A, and doctors from health care system B only accept insurance B. Sure, you can “choose” another insurer, but then you can’t see any of the doctors you’ve built relationships with. Choice, indeed.
[0] Technically physicians can opt out of accepting Medicare; in practice I’ve never found one who opted out of Medicare that didn’t simply refuse all insurance.
