PubSub hidden functionality not available to devs?

Is there a reason PubSub doesn’t allow us to listen to topics such as ‘activity-feed-broadcaster-v2.######’? It seems like it would provide a lot of functionality and doesn’t require a dev to setup a server just for follow notifs or hosts? Cheers, channel points, subs, and gift sub are already included in pubsub, but things like Raids and hosts are missing. If this has been discussed before I could check out that thread but the search doesn’t come up with pubsub topics.

This is developed to run the Twitch website itself. They do not public these hidden topics because they don’t support 3rd party use. If they want to change fields, or just stop using it altogether, if they are private topics, they do not need to announce changes or put a decommission period on them. If business requirements for the website change tomorrow, they can update the pubsub topic as needed instantly.

I understand this much. I only pointed that particular topic out because the functionality exists and can easily give us a dev topic for such functionality. I’m more wondering why they seem to be favoring Webhooks over the pubsub, they obviously have functionality to live feed follows, hosts, raids etc (not really concerned about raids since you can get that from irc) but are choosing to go the route of webhooks. Webhooks are arguably more expensive for the developer than pubsub and i would think more developers could utilize pubsub.

Pubsub for Eventsub is Soon™. Legacy pubsub most likely will not be updated with new 3rd party topics

No one requested it (it being this topic/data type/resource) via Uservoice:

https://twitch.uservoice.com/forums/310213-developers

If there is functionality missing that you desire, you shold raise a UserVoice stating what you want and what your use case is!