Believe people more.
If you knew Arabic, you would know that "Qaeda" as a word has strong insinuations of structure and hierarchy. It is in the name,
For most of people, it's no more than a product of their imagination.
You've believed that nonsense. People can lie, you know.
I know people that bumped into quite a lot of salafist organizations that would later affiliate with Al Qaeda, they were well organized and had funding as well as structure and hierarchy.
In any case, a few dozen angry disenfranchised seminary students with a leader as well as en executive council and multiple branches is more of an organization than Antifa is. I know that Al Qaeda has declined a lot, but I know for a fact that it was much more than what you claim it is at least at the time.
There is absolutely no comparison you can make between Al Qaeda and Antifa or Anonymous.