All of the above and none of the above.
The bottom line of a groups success is just that. The bottom line.
Are they making a good bit of money then they are a success and doesn't matter if it comes from youtube views, concerts or even just CFs. The person that tanks with streams but sells 20,000,000 albums will be laughing at your "But they don't chart" comment as they drive by in their Bugatti Chiron.