I disagree, a lot of people aren't doing Ultimate because they are waiting for people to clear it, to see if it's possible. There are those who have time to grind it out and try and others who will try once the guide/methods of completion have been shown.

Basing the success of "Ultimate" content from not even a week of being live is a bit of a leap in assumptions to make. If you honestly want to know the success of Ultimate you should be looking at it a month from now, not 5 days later.