I don’t think it could.

The client doesn’t have access to all the videos, it’ll have to query the (distributed???) platform to find matching videos.
And the platform is gonna need to serve up some kind of metadata for the client to track (are hashtags enough???)
And the platform is gonna need to be keeping stats on the videos for the client to match against
And what would that query even look like? A gargantuan weighted map of hashtags? I can’t imagine hashtags alone would be enough.