I would be surprised if they weren't, or at least if they couldn't be linked quickly if stadium security wanted to, like if there was a potential security threat and they wanted to scan the stadium crowd for "persons of interest".
Unfortunately, the stadium ceiling cams that I’ve seen (and I’ve seen some of the ones in Cowboys Stadium) don’t have much by way of onboard logic. The control booth may have the ability to do FR and datalink them together as an array, but the Chinese unit can do all this without a control booth or external support as well as network with others in the area without external support.
It’s the difference between having to lug around a 1970s component Hi-Fi system versus a Bowers and Wilkins Zeppelin Bluetooth speaker connected to your smartphone. There’s a lot of things you can do with a miniaturized self contained device in seconds that would take hours or days of setup with the older tech.