Right now someone's taking a picture of their butt and posting it online.
In the time it takes you to read this sentence, someone's taken a picture of a friend, colleague or loved one's butt, and (consensually ofc) posted that online too.
There's every kind of butt on the internet. Any shape, any size, any gender, any ethnicity, any age, all of it, variety unlimited.
There are already so many butts on the internet that if you made it your full-time 9 to 5 job to look at all the butts, one butt every second, 5 days a week and maybe a couple hours of overtime near the holidays for extra present money, you would die before you'd seen them all.
In fact, the rate of buttposting is increasing all the time - by the time you die, there may even be more new-to-you butts online than when you started. It's an unending task.
And yet people look at Twitter.