I think the methodology is flawed (they didn't check for waivers or authorizations, or even for structure height at flight locations), but it's exactly the kind of press that leads to regulatory outcomes that further restrict our ability to fly (for both pleasure and business). The study itself (here, p. 20 (p. 22 of the PDF)) notes these weaknesses, but without any discussion of them. I operate under a Wide-area-authorization, and all my local flights (every one I've flown, in fact, except one) would be found by this study to be in violation because LAANC doesn't operate at my local airport. I wouldn't care to guess what the ratio of waivers/authorizations is, but mine was incredibly easy to obtain, so I think it's probably not negligible.