"while Apple Podcasts has shown no willingness to push video at all."
Back in the day, Apple used to actively push video podcasts.
Had they leaned into that, perhaps YT wouldn't have such a grip on the video space.
The advantage Youtube has is that they host the video, it removes a lot of the overhead. Apple requires a separate RSS feed for video I think so that requires the creator to pay hosting or self host.
I listen to several podcasts that put the video out on Youtube and a few upload the video to Spotify but not Apple.