Why not both? Tiktok is great for reaching new audiences (look what it did to Zmod and HOMIGRAD. Whatever you publish on tiktok can be published to Youtube Shorts. The short format algorithm is absolutely cooked and will boost you a lot.
Facebook videos is slept on especially since somehow they end up top results on google rather than Youtube lol, the only downside is you have to title em like you're a news channel.