I don’t know anything about Hurd besides GNU working on it when Linux came out. What was sexier about Linux? Was Hurd any good?

I don't know how "sexier" has anything to do with the topic.

Linux was available now. Hurd ... was not. Still isn't.

Hurd is based on a microkernel architecture, which was/is enticing because (quoting https://en.wikipedia.org/wiki/GNU_Hurd ), "In theory the microkernel design would allow for all device drivers to be built as servers working in user space" and "According to Hurd developers, the main advantage of microkernel-based design is the ability to extend the system: developing a new module would not require in depth knowledge of the rest of the kernel, and a bug in one module would not crash the entire system."

There is a long debate about microkernel vs monolithic kernel. See https://en.wikipedia.org/wiki/Microkernel for one such summary.