Lots of players don't want to go to California. Highest taxes in the league I believe.

Assuming the rumors are true (they were both reported as unsubstantiated with no evidence to support them), the reported reason behind both players declining to waive their NTCs were due to geography. Neither wanted to go to the West. It has nothing to do with LA or the culture.

Eh, I think making assumptions on culture based on rumors might be the problem.

If we follow rumors both goalies have been rumored to have shut down trades, not just to LA.

But if it's true there are several factors, and just pigeonholing bad culture doesn't make sense as LA has consecutively obtained and signed long-term extension for several notable players I think it could be any number of factors if there is truth to the rumors:

1. Money / Taxes / Distance From Family / East Coast Bias / Usual Reasons
2. The Kings have a first-year pro top-5 goaltender in the AHL who came to LA to be a starter, not exactly what you want as both those goaltenders will be moved out because younger options are replacing them
3. The Kings are a playoff team that cheaped out on goaltending because they have a strong defense
4. No familiarity with the system/coaches/players

Canada is higher.

Toronto, Ottawa and Montreal are all 53%, most expensive, followed by the 3 California teams at 51.75%. Their money probably goes further in Canada though.

I'd be surprised if Markstrom turned down the Kings. Gee, I'd be surprised even the Kings wanted him unless there was retention.
Why would Ullmark leave the Bruins?

Ullmark has the entire pacific division on his NTC. It’s purely location, location, location.