Because there have not been million people with different levels of skills poking and prodding Mojolicious into good, bad, ridiculous, disgusting, ugly and beautiful uses, posting on Stackoverflow, getting answers, getting smacked down, or getting those things marked as known bugs. I use code to achieve a business objective, not to create a beautiful code or use a wonderful framework.
Just framework itself is not enough - it needs to have skeletons for services that would handle common edge cases -- database failures with automated switch to standby, internal request queues with retries, configurable. Clean interface to external configurations that should be changeable in-flight without a restart; patterns for interfacing with other systems, etc.
> Yes, Perl's threading support is terrible,
Some of the basic crypto modules and modules that use those basic crypto modules are not thread safe. In 2019. Modules that were written a decade ago. I'm not interested in figuring out those bugs in production.
I wrote a pretty complex API using Dancer. I'm not going there again.
Yes, Perl's threading support is terrible, and I do wish it was as effortless as in Raku. But you'd be surprised how often you actually only need an event loop and non-blocking implementations, and for the rest of the time there's Mojo::IOLoop->subprocess or IO::Async::Function to provide a thread-like model with efficient forking.