Ha! That’s funny and many small online companies such as CNN, NY Times, the whole family of CBS Network news sites, many universities, some financial companies, etc. wouldn’t think much of that statement.
It IS designed for amateurs. Those companies you name have probably undergo heavy modifications to the WP code to make it perform as they want. They won’t apply your updates as they are available. And I don’t think they will give the community anything back any time soon.
So stop saying that big companies find the WP code perfectly suitable for their needs. It is just self-contempt.
I do like WP as a project, but it has flaws (like the URL generation) that are not being addressed. This leads to modified WP code, which leads to updates not being applied, which leads to a poor WP experience.