A has a solid proposal and they're a known good quantity on the "speaker circuit"
B is a newcomer and their proposal looks really interesting too--maybe even more so--but we don't know them so maybe A is the safer choice
(I'd argue that this is the way that a lot of conferences have historically operated and many still do to some degree--which is OK to a point. You don't want to exclude traditional crowd-pleasers.)
But maybe if A's proposal is just solid, it wouldn't hurt to reach out to B for some additional information and to offer mentoring rather than just go with the safe easy choice.
Sure, but to the extent that you're going with the safe easy choice, you're not deciding based on merit. There are cases where that makes sense, but the ones where it doesn't aren't a problem with meritocracy; they're a problem with giving up on meritocracy.
A has a solid proposal and they're a known good quantity on the "speaker circuit"
B is a newcomer and their proposal looks really interesting too--maybe even more so--but we don't know them so maybe A is the safer choice
(I'd argue that this is the way that a lot of conferences have historically operated and many still do to some degree--which is OK to a point. You don't want to exclude traditional crowd-pleasers.)
But maybe if A's proposal is just solid, it wouldn't hurt to reach out to B for some additional information and to offer mentoring rather than just go with the safe easy choice.