Check out any other Python framework and they may have a decent api, but on the inside it is messy and confusing.
This is a really disingenuous generalization. If it's not Flask, it's messy and confusing? Telling every framework developer who's not the author of this one library that their code is crap not only isn't a great way to be taken seriously, it's wrong and just kind of mean.
The natural state of any large codebase maintained by multiple persons over multiple years is to be messy and confusing. Therefore it isn't a slight to anyone to state that the Flask devs have been able to keep their source code much cleaner than the average.
This is a really disingenuous generalization. If it's not Flask, it's messy and confusing? Telling every framework developer who's not the author of this one library that their code is crap not only isn't a great way to be taken seriously, it's wrong and just kind of mean.