Looks like RWSL did indeed warn for this accident. So maybe RWSL needs to be made more obnoxious (or just speakers in ground vehicles that blare when you're approaching a red RWSL threshold).

And, of course, training to really actually comply with RWSL.

There's a lot of similar history from early TCAS where it failed to save the day because of human factors, training issues, and tuning.

Also: ASDE-X did not alert.