I'd say it depends on your uses.

If you're an organization looking for a platform in which to publish your videos so that they can be spread in your newsletter/social media and embedded on your website, it's probably a very good alternative.

If you're a content creator who runs on donations and has a dedicated following already, it might be good. And as the fediverse grows, it will only get better.

For a lot of the content creators who live off engagement and clicks, it's much less likely to become a viable alternative. The kind of content people will watch for hours, but that nobody would ever consider paying for.

I think it's not about one platform replacing all of YouTube, but about providing viable alternatives for specific uses.