vector 361
All true of course, but we are where we are, primarily because of several nasty mid airs in US airspace. All it requires is for the FAA to say that all IFR traffic should be separated from known VFR traffic by 1000 feet. Simple.
Incidentally there have been TCAS problems at DEN for a while, with apparently local operators going to TA only, which in my company (Boeing approved manual) is strictly not permitted unless called for by a checklist.