Keep in mind that genetics plays a large role in it. Some people are incapable of getting that phat bubble butt no matter how hard they try. For that coveted shape, that lots of gays see as the holy grail, you need your body to naturally store a decent amount of fat there even when the rest of your body is slim. This is like the same dilemma most women face. Put on weight and have bigger boobs or remain thin and have a much flatter chest. Breast enlargements are extremely popular because the vast majority of women do not have naturally big breasts on a slim waist.
Imagine that you're working out every day and you're ripped all over but, no matter how hard you try, your butt is small. Sure it's extremely toned but it just won't get that big, smooth, round shape people like Daniel Montoya manage without even trying. By smooth I don't mean a lack of hair I mean it looks like one big bubble rather than you're so trim/toned that you can see all the individual muscles and nothing really jiggles. It's the fat that smooths out the appearance and gives you the jiggle. Your only option would be to eat lots/get fat, and lose the definition elsewhere on your body, or have fat injections. It's even possible that Daniel Montoya might have had fat injections already, which makes the situation even worse. Gay men trying to live up to the bubble butt ideal when the ideal isn't even real. Social media doesn't help with this either as lots of the popular guys on there are enhanced with photoshop.
Sometimes a particular physique isn't in the genes for you.