Blizzard may well create boss timers, eventually. With them they've been able to tune fights much tighter because we, as a community, can see that the fights are feasible based on our mathematical calculations of how to do what and when. Blizzard would have to allow larger room for error. They don't expect you to have a boss mod but almost no one who plays at any competitive level would raid without one.
Question is: Could Blizzard come up with a 'better' boss mod? If anything it's the UI interface they're working on. I'm sure everyone has their dbm/bw somewhere different on their screen. Bars are different sizes, what information you track, etc. Making it possible to function as well as those two giants is going to be no easy feat. I still use the add-on Grid even though Blizzard has their own now. I just feel comfortable with it.
It occurs to me that those mods have existed for too long and there is little possibility of removing them without watching the skill cap drop significantly.