It's OK to suck at math; you won't be using much anyway.
I'm not sure how this stereotype got instilled in
me, but I'm slightly embarrassed to admit that I was
surprised to discover how little math is involved in
day-to-day programming, ...
That depends. The amazing thing is how knowing math can help in so many unexpected, tangential, apparently unconnected ways. Time and time again the guys I work with do stuff that would be easier if they knew more math. When I pair with them they frequently say that they wish tehy knew more math.It's OK not to have a PhD, it's OK not to have a degree, but at least knowing about, and having a good, intuitive grasp of what goes on in topology, linear algebra, analysis, graph theory, game theory, logic and more is immeasureably useful.
Unless you're doing the kind of coding that really doesn't require design or algorithms or data structures or communications or database work.
I've never used stuff I did in my PhD, but time and time again, continuously (and I use the work correctly, I don't mean continually) I've used the stuff I learned on the way that enabled me to do my PhD.
Learn more math. It will be useful, even if only to give you the option of rigorous reasoning.