A sold out Rolling Stones concert doesn't suddenly make them more relevant.. Green Day has the luxury of having a fan base that's not entirely dead of old age yet.
To be relevant usually speaks to some kind of broad social impact or defining of a culture. You might argue Green Day did that back in the day, but do they really continue to? A lot of people willing to pay to be entertained by their performance does not imply relevancy.
Idk, not many people can sell tens or hundreds of thousands of pricy tickets to see them do their thing for 90 minutes. ¯\_(ツ)_/¯