No, pointing out that your claims are conceptually false is a fine look.
It's not about things Mozilla could theoretically do to block you, it's that they require you to proactively get their permission to run an extension (in a prod version of the browser on an ongoing basis, which I think is reasonable table stakes). Here's their official docs for self-distribution, i.e. not using the AMO at all: https://extensionworkshop.com/documentation/publish/submitti... Notice that step 1 starts with giving Mozilla your extension to approve of, step 4 goes so far as to say that if your extension doesn't pass their checks then
> The message informs you of what failed. You cannot continue. Address these issues and return to step 1.
then step 7 is make sure Mozilla reviewers can read your source code, step 9 is wait for them to get back to you, and step 13 is download the XPI that Mozilla has approved to be allowed to run in their browser.
So yes, you absolutely need Mozilla's approval to publish an extension, even if you self-publish the XPI after they've blessed it. If they do not perform the action of signing it, they don't need to change any source code, it won't install. It may be true that in this case they have given that approval, but that doesn't invalidate the general point, and this is a fundamental restriction, not "language-lawyering".