Since most of these ADS-B collection sites are patchworks of unofficial/best effort, that seems like a great attack vector for nation state-level spoofing to interrupt flight planning, capacity planning, other tertiary air transport operations, and make civilians nervous. It's analogous to "hobby" code running key infrastructure of the internet without serious processes and auditing, testing, and verification.

It would be far better and more reliable to have the FAA do it by providing authoritative single source of truth as (selectively) open data rather than depend upon the whims / greed / sloppiness of an over-privatized utility. ATCs need and/or have this data anyhow, so in the future, it should be provided.

How do less neoliberal European countries do it?