I doubt you actually asked any lawyers who know this stuff.

While GDPR did raise the threshold of valid consent, the interpretation before the GDPR was nowhere near what you describe here.

There are authority guidelines and sanctions predating the GDPR on this.

I asked a lawyers during a conference that discussed privacy and law. I initially asked if a 50 page document was fine, which they said was not, but then lowered it to 30 and they said "sometimes" without any irony in sight. After an additional discussion they said that even if people did not read the document or had the ability to understand it, it would still count as consent.

I have also talked personally with politicians who was involved with the work of writing GDPR, and the people who wrote the ePrivacy Directive has reportedly said that lawyers interpretation of consent was beyond the imagination of the original intent of the directive, which is why GDPR now require freely given informed consent in contrast to the old consent.

You asked the wrong lawyers, at least for the US. The FTC's case against Sears in 2009 made it clear that consent to a privacy notice isn't valid if the privacy notice is buried deep in a licensing agreement, even if the notice is correct.

They are referring to GDPR. I do not see how any US ruling applies to that.