Position yourself as a video creator and post your videos also to Instagram (when possible) and to Vimeo. Seed free / back catalog episodes via a torrent. Run a mailing list announcing and discussing your videos, with some premium content for paying subscribers only. Maybe have an X / SkyBlue / mastodon feed with more compact announces, comments, and high-virality short clips from your longer videos.
Cross-link and cross-reference all the channels of your presence. Make your brand recognizable across the publishing methods. Gently prod people to touch more than one channel of your video distribution, just to get the most avid viewers acquainted with several.
Yes, this is significantly more work. It also may bring significantly more results if your videos are good. This gives you a much stronger assurance that your brand and your following will not be lost, should you lose access to YouTube / Instagram / Vimeo / X / whatever other platform. Commoditize your complement, as they say.
It seems these days, most Youtube creators are at least somewhat aware of the problem and have websites, discord channels, patreons etc. While I still think many would struggle if they lost their youtube access suddenly, they do have additional channels to reach out to at least part of their audience.