What would the real alternative be? A single nonprofit in every market collecting operating donations for just that market?
There are some TV translator clubs around the US that are supported by voluntary subscriptions, who also insert linear streams of hyper-local content and public-access content. I would find value in that, and would consider supporting. (Those translator clubs use low power OTA transmitters, but the Opinion and Order seems to put them on the same footing as a local OTT service)
An organization using the exemption of course wouldn't/couldn't implement a paywall.