I get the logic, but I also think it's a bit of a stretch. They may unknowingly consent to that, but you have to go out of your way to read the Terms of Service to consent to that specifically and I would imagine most people are just trying to provide or fix lyrics so others can easily find them, not so Genius can have them exclusively as that's certainly not how most users think.
It also brings up a good point on whether Genius should have exclusive rights to something in which they gained that exclusivity from uninformed "consent" of their users' efforts. If transcribed lyrics are copyrightable, why should Genius hold that right and not the users' when Genius are claiming that right by hiding their Terms of Use as a tiny link made to seem like it's part of the website's copyright/trademark notice[0]. I'm inclined to believe that Genius are purposefully being deceitful in how they link to their Terms of Use to avoid flack.
It also brings up a good point on whether Genius should have exclusive rights to something in which they gained that exclusivity from uninformed "consent" of their users' efforts. If transcribed lyrics are copyrightable, why should Genius hold that right and not the users' when Genius are claiming that right by hiding their Terms of Use as a tiny link made to seem like it's part of the website's copyright/trademark notice[0]. I'm inclined to believe that Genius are purposefully being deceitful in how they link to their Terms of Use to avoid flack.
[0]: https://imgur.com/DP5fmre