Is it better to max TSP or diversify into an HSA?

My goal is to try to max out my TSP contributions, but I’ve also just signed up for a HDHP that includes an HSA. Would it be worth it to reallocate $6k/year to my HSA that would normally be going to my TSP.

It seems everyone talks about how great HSA’s are, but perhaps it’s really just the case for those who are already maxing out their TSP’s and are looking for another way to optimize their savings and reduce their taxable income?