They are primarily a hardware company. As an example, their Pocket Cinema 6K camera costs $1,995 and includes a full DaVinci Resolve Studio license. Also, their new ATEM Mini Pro ISO effects/recorder/switcher/streamer box, can generate a Resolve project with all the transitions and cuts one did in the live stream, that can then use the full res media recorded in camera as the starting point of a higher end version of the stream.
Their free version has some limitations, but most non-pro users will never hit them. For those who want the full version and do not plan to buy a camera, the full version is $300, and has included upgrades. It is also available on the Mac App Store.