[delecti]

Depending on your threshold for "long form", nearly all of them:

Reddit has supported direct video uploads for literal years, maybe 5 years at this point, and up to 15 minutes in length. TikTok also collecting your data doesn't change that it hosts videos, and supports up to 10 minutes, and that limit has been increasing as they try to be a more general purpose video platform. Instagram hosts pictures, but also livestreams and videos, both short-form (a few minutes), and long-form (IGTV supports to an hour). Twitch is the only one that seems to clearly not support long-form video content, but even then it's still a competitor because that's not all Youtube does either.