You (and some others) might find a need for a really fast shutter speed, and be willing to pay a premium for it, but I don't think the majority of photographers would, apart from those pro/semi-pro niche photographers who want waffery thin DoF. There have been useful innovations in camera technology that have been swiftly discontinued due to them costing money and not being hugely appreciated by the majority (and/or criticised by a vocal minority).
Take Canon's incredibly useful eye-controlled AF point selection feature in the 1990s for instance. For those who don't remember that; you just looked at the AF point you wanted to choose and the camera tracked what you were looking at and selected it instantly for you. How cool was that? And that was around in the 1990s! However, some people couldn't get it to work for them (although you could easily turn it off and use the camera as normal), and moaned about it. It cost Canon a lot of money to develop and wasn't cheap to include in a camera, so they dropped the feature completely.
As I said above, if a feature costs money and doesn't significantly sell more cameras, then a manufacture just won't continue to include it as standard, but might include it as an option for a premium price on a pro-grade camera for those willing to shoulder the cost and who actually need and appreciate such a feature. Although, if mirrorless technology reduces the cost enough, they'll probably throw it in, providing it doesn't significantly reduce the working life or durability of the camera.