I think a lot of what have you written can be solved software-side. Good Database should be no excuse for bad code.
I do not think MySQL is a technological debt as in 80% startups moving to the different solution is cheap and non-problematic. The LAMP is good enough and quickest/cheapest for the majority of tech companies.
I'm being perfectly fair in being critical of a software which claims to be doing those things.
You can solve issues in your application if you know there will be issues like these, knowing the pitfalls and drawbacks of a technology is certainly noble- but if you do then why not choose something that follows principle of least surprise. (There might be reasons).
I would never claim that you should move everything from MySQL if you use it. However if you care about data consistency ensure that you change the defaults, engage strict mode, ensure that your application has no bugs in handling data.
This is actually hard to do correctly, it's overhead in development that you shouldn't be caring about. Just choose something that has sane error conditions and the problem vanishes.
I do not think MySQL is a technological debt as in 80% startups moving to the different solution is cheap and non-problematic. The LAMP is good enough and quickest/cheapest for the majority of tech companies.