I don't think most companies are maliciously breaking unsubscribe buttons, but there are a lot of websites that don't work on some browsers, are badly maintained to the point of being unusable, are confusing, or simply don't work because the people that maintain them aren't professional web designers.
When your website is broken and you continue to charge me money, I don't think the onus on me to report the broken website, help your (maybe non-existent) IT division to find the bug, wait around for them to come up with a fix, and then help them beta test it. I should be able to file a ticket and say "I don't want your services please stop taking my money".
And how would this case work against you in the FTC’s legislation? Seems pretty clear that if it doesn’t work to unsubscribe but it would work to subscribe then it’s against the ruling.
If the website can’t actually add subscriptions then good luck to that company surviving!
When your website is broken and you continue to charge me money, I don't think the onus on me to report the broken website, help your (maybe non-existent) IT division to find the bug, wait around for them to come up with a fix, and then help them beta test it. I should be able to file a ticket and say "I don't want your services please stop taking my money".