Certainly. I have heard of a number of senior execs who really hated public speaking (even when they were very good at it given sufficient rehearsal). But I agree in general. If you have a public/customer-facing role you're going to find it exhausting and probably not going to be great at it if it is uncomfortable/unpleasant.

I'm certainly not the classic stereotype of the outgoing sales rep (whether that's a fair stereotype or not) but that didn't keep me from attending a ton of conferences, customer meetings, and giving public presentations.