Elon Musk wants tweet creators to earn money from advertising in the replies. However, an active Twitter Blue subscription is required.

Elon Musk also wants to show advertising in the replies to tweets in the future, instead of just in the timeline. This could be financially worthwhile for the authors of the tweet, as Bloomberg reports with reference to the owner, since Musk wants the tweet creators to share in the advertising revenue.
Twitter Blue is mandatory
However, the matter is subject to one condition: the Twitter user who wants to earn money from advertising in the replies to his tweets needs an active Twitter Blue subscription. In the US, the price for the subscription is currently at least 8 dollars – iOS users who book the subscription via Apple’s App Store pay more.
According to the report, Musk has not yet announced how high the participation in the advertising revenue could be. But he is working on ensuring that his company’s “premium product” meets with more acceptance, it says there. Previous benefits of Twitter Blue include correcting tweets after the fact, sharing longer videos, and prioritizing content.
The annual plan costs 7 euros and is billed annually (84 euros) – alternatively, the company offers the monthly plan for 8 euros. Some of the features associated with the subscription are “coming soon” and will not be available at launch.