How can I speed up HTML5 build times?

Having used Unity quite a bit, I was unpleasantly surprised at the build times for Unreal. Even native compilation for a handful of C++ classes with barely any code can take 5+ minutes when a header is changed. When packaging for HTML5 on a Windows 10 machine with a Ryzen 7 and an SSD (and this optimization turned on), compilation times are upwards of 20 minutes.

Considering how little is actually in my game at this point, I was shocked at this number and assumed I was doing something wrong. I looked around online for an explanation, but I’ve found nothing. Is there anything that can be done to speed this up? It makes using Unreal to do anything with C++ feel like torture.