tl;dr: If there's no reason to get an MBA as a promotion-track engineer, then not only will none of your promoted engineers will have MBAs, none of your promoted MBAs will have practical experience being a great engineer.
They wouldn't, of course. And that's really the problem.
If you don't have mid-level technical managers with MBAs, you don't get to promote/hire VP-level technical MBAs.
An MBA does teach a lot of valuable skills. As many smart technical founders/leaders have crashed up against the corporate rocks of running a major division/initiative as business leaders failed due to distance from execution.
Right now though there's no role, and no opportunity, for a mid-tier (post-MBA) capital-E engineer. So there will be no MBA-toting, engineering-aware VPs.
Without business-fluent engineers (or engineering-fluent business folks) companies are deprived of interdisciplinary innovation. You get financial programs which ignore technical needs, and great inventions which don't have a market. Promotion which doesn't represent reality and deals which can't be executed.
Most of the frustration engineers have with business people is not that business folks can't do business well, but that they don't do so understanding the underlying technology.
And until there's a reason to want a techie MBA (or business-y Eng) at a sub-VP level, this isn't going to get better.