Has anyone dealt with this? I also don't really enjoy managing people. I enjoy being a skilled sole contributor. But, this will limit my growth eventually and monetary value at work.
I feel like this is the real issue, not the public speaking specifically. You can do lots of things to become comfortable speaking in front of people, but the main crux is that you're looking at a career track you don't like, because it pays more. I'm the same way. I just don't like managing. I can do it if I have to, but every aspect of management to me are the worst parts of any job, so to aim for doing more of it doesn't make any sense for me.
So yes, I have made the conscious decision to limit my upwards mobility by not going into management. It's ok to do this if it means you'll enjoy your career more. Don't feel like you have to constantly be moving up (which isn't to say you shouldn't be constantly trying to be BETTER). I have family members that look at me like I'm the family idiot for working hard at NOT moving up (because if you're good at what you do, you do have to fight to not be pulled into management). But I'm ok with how much I make, so I'm ok with hitting a ceiling. Nothing wrong with that.
But having said that, the ceiling probably isn't where you think it is, or as firm as you think it is. The last couple years I thought I was at it, then this year I'm making 25% more than I did last year. If I switched companies, I could probably make even more. I've been at my current company for almost 6 years, which in IT usually means I'm getting way underpaid compared to if I job hopped. But I like where I'm at, so I'm ok with that too (for now anyway).
Bottom line, don't feel like you're making the wrong choice by not climbing the ladder if you don't want to.