Difficult, not inconvenient.
Because it allows things that are difficult, like writing your own memory allocators.
If you don't like working at that difficulty level, then C programming isn't for you. And that's fine.
It doesn't allow me to write my own memory allocator, it forces me to.
This line of argumentation reminds me of this:
Advertise and promote a shortcoming or a fault as a virtue.
For example, ultra-cheap single-use film cameras are advertised as "No Focusing Required." The truth is, no focusing is possible, because those cameras have cheap plastic fixed-focus lenses that won't move and can't be focused. What is a serious shortcoming for a camera — the inability to properly focus on the subject — is sold as a convenience: "You don't have to bother with focusing."
https://orangepapers.eth.limo/orange-propaganda.html#make_vi...