The API is cheaper than having to raise services to send messages to requesting people
API can be cached easily
Outbound HTTP POST cannot, even more so if the receiving party errors and it has to be retried.
Most people replying on the forums are no Twitch Staff btw.
I for sure am not.
But EventSub has to handle/operate/work multiple topics.
YouTube pubsubhubbub only has to optimse for a single topic as they only offer a single topic.
No, it’s not.
The Revoke Topic is a single subscription costing 1 point.
And it notifies for all revokes on a given clientID.
You don’t create a revoke subscription for each user using your App.
Revoke only accepts a clientID as a condition not a user_id.
So for 30k guilds, using one user token per guild thats ONE REVOKE TOPIC TOTAL. As it’s for your ClientID not ClientID/userID Pair