I agree with you to a point. This is the career path they've chosen, so my empathy only goes so far. If you want to earn, you have to work. However I also understand that shit is often out of their control. Guys getting injured, staph, family emergencies, etc. can all prevent that type of a run from happening.
More importantly though, MMA politics and matchmaking fucks careers far more often than most people realize. Holland has been getting the right fights for where he's at. Maybe it's luck, maybe they want to build him up. Either way though, plenty of guys have tried to do what he's done but got knocked out in the process and then weren't in any condition to fight multiple more times that year, or they faced any number of other issues that prevented it from happening.
All I'm saying is if it was that simple to do what Holland has done, it wouldn't be noteworthy.