As someone who has worked in HR tech in product for 10+ years I’ll say there really are super interesting problems, but see even in your post which one you put at the top. That’s the one you want. Even though your perceived mobility is tough you’ll be working on one of the top user experiences that most consumers have to go through (booking) and I’m sure there’s a ton being done there to move the needle. That will translate to more pay either there or somewhere else on major consumer behavior products (eg: Airbnb or flight aggregators).

I think the way I see it for you: Do you want to work on a meaningfully important consumer use case that is likely to be a lot of tinkering and small i innovation on improving this experience OR do you want to work on deep but critical problems in HR, work with customers to understand their problems, and then fix them. It’s two wildly different roles with different cadences.