With the high level of effectiveness that the vaccines started with, there really isn't a need for a booster for the original variant. Even though the vaccine producers are saying so (what a surprise they would say that), the CDC isn't. They're following the science which is recommending a booster for immune-compromised folks who have a clear reduction of antibodies compared to others.
The problem is the variants. The vaccines start off with a lesser effectiveness (but still pretty effective). And future variants may prove even more resistant to the current vaccine.
The real reason for boosters will be, I predict, an altered vaccine that targets the new variants more effectively.
Either way, the U.S. administration can announce plans to do boosters, but it will still take the FDA to approve it. And I don't think they're in the mood to allay first world irrational fears over a slightly less effective inoculation by rushing the science with regard to boosters while they're still trying to vaccinate children and the world.