Premium is the ticket. It is not the audience. The checkmark gets you into rooms and into X's payout program. The 500 verified followers and the impressions are still yours to earn.
What the subscription actually buys
A public account with a Premium checkmark can sign in to XPacts. Accounts without one stay out. That is the whole room: people who pay X, post in the open, and can have a follow checked.
The same subscription is what X asks for before you can apply to get paid. Original Content Rewards, the program that replaced Creator Revenue Sharing, requires an active X Premium, Premium+, or Premium Business plan. X Premium Basic counts when someone views your post. It is not the plan that qualifies you to join.
The numbers behind getting paid are on how to get paid on X.
What it does not buy
The payout program also wants at least 500 verified followers, and at least 500,000 Home Timeline impressions from verified users in the last 90 days. Impressions on replies do not count. A checkmark does not produce either number.
Bought followers, auto-follow, and a pod of people liking posts they did not read do not fill that gap. X's rules tell creators not to use tools that artificially generate follows, views, or likes. A follower who is not verified does not move the 500.
When it is worth paying
Pay for Premium if you post original work and you want other Premium accounts your own size to actually follow you back and stay. The first bar in the payout program is verified followers. A pact is one of those: both of you have a checkmark, you follow on X yourselves, and the follow is checked for a month.
Skip it if you wanted the follower count to move on its own. The subscription is a poor purchase for that. Growing the account is still replies, posts a stranger can answer, and mutual follows with people who would have followed you anyway.
That part is written up in how to grow on X under 10,000 followers.