It very much is a typical big corp, and OP is correct. It's easier to ship something on a new domain, using AWS and a bunch of contractors, than to add a subdomain to facebook.com or some other top-level domain
Not to mention, the "Ordinary big company red tape" didn't stop Coca Cola from hiring Colombian death squads, Nestle from draining the Great Lakes and selling it back to it's residents, nor Hershey's from making chocolate from cacao farmed with child slave labor.
Relative to the rest of FAANG (or even Fortune 500), Facebook might have the least blood on their hands when everything is said and done.
um... did you sleep through the last 8+ years of handwringing about election interference, Russian / state propaganda, live streaming massacres, addiction / mental health effects of social media, particular for kids? I can't imagine the other FAANGs come close
If platforming disinformation and enabling internet addiction is equivalent to criminal complacency, then Microsoft, Apple, Amazon and Google all have crimes to answer for. Facebook has shit the bed more times than they can count on two hands, but unfortunately that's kinda the table-stakes in big tech.