I don't think there will be any "further reluctance" among the anti-vaxers regarding boosters. It's the same reluctance as before. They didn't get the first vaccine, and they're not going to get the boosters. Not willingly anyway.
Unfortunately I suspect we'll also see diminishing returns from the already-vaxed. I'd be shocked if we get 100% "return customers" when it's their turn to get the booster.
Personally of course, I got the vax as soon as it was readily available to me, and I'll do the same for any boosters that come along.