It is actually documented, surely you must be confused?
You have the docs with extensive examples, you have a free book, and the whole framework is typed and all configuration options and the individual components referenced: https://symfony.com/doc/current/index.html
And if you use PhpStorm with the Symfony plugin almost everything gets intellisense.
I think his complaint is that a lot of the Symfony docs don't simply say what things are/do, they instead inform via examples. Which means you have to parse the examples first to understand what's going on.
Yes, "documentation" implies a curated and complete reference, not a collection of code snippets that may or may not apply to your current problem and version of Symfony.
(No, random posts oт Stackoverflow and generative AI responses aren't a replacement for documentation either.)
You have the docs with extensive examples, you have a free book, and the whole framework is typed and all configuration options and the individual components referenced: https://symfony.com/doc/current/index.html
And if you use PhpStorm with the Symfony plugin almost everything gets intellisense.