The alternative is just that cabal will continue indefinitely to try to install completely broken combinations, and more people will be driven to a fixed package set like stackage LTS.
Most of these problems are caused by people being too optimistic about upper bounds and when they realize their mistake and upload a new version, they'll often leave the old versions with the lying bounds intact, which causes cabal to pick old versions without bug fixes, and then give strange build errors.
To my knowledge, the few cases where Herbert has actively done a patch to the .cabal file like this without author communication is because the package is in very very widespread use and the author has been incommunicado for many months. As I recall, Max Bolingbroke has a some packages that fit this bill.
At least in my case, and in the case of the Haskell core libraries, Herbert has been very conscientious about talking to me, finding problems, auditing what builds across all versions of GHC in recent and not-so-recent memory, and working with me to find the best fix on a case by case basis. He has my explicit consent for any tweaks he has had to make to the build dependencies of my packages and has worked with the core libraries committee very closely for patches to the core libraries.
If you have an example of a package you've written that he's patched that you'd rather he left alone, I'm sure he'd be happy to oblige. I am, however, as of yet unaware of any such overreach and I'm rather disinclined to view the enormous amount of effort Herbert has poured into keeping the ecosystem working smoothly as anything but a good thing. The price of doing nothing here is quite high.
-Edward