I blame the networks for the match-ups. Klitschco, Mayweather, Cotto , Pacman, Canelo , GGG , Kosolov are all big draws so they match them up with Cherries to continue their winning and popularity. The popular fighters won't fight a real challenger and risk losing their appeal to the masses.
First, learn to spell cherry correctly. Klitschko has completely wiped out his division so to say he's cherry picking fights is absurd. Mayweather has fought Pacquiao Canelo & Maidana twice in recent history. Pacquiao just fought Mayweather who's #1 p4p so that's quite the opposite of a cherry pick. Cotto has fought some cherries but is signed to fight Canelo next which is a great fight. Canelo cherry picked Kirkland but has taken tough fights besides that recently in Mayweather and Lara. GGG has fought cherries only because Cotto is not anxious to fight him and is now fighting Lemieux in a solid matchup. By Kosolov I think you mean Kovalev who has all belts besides the WBC which Adonis does not want to risk as well as network and promoter issues between the two. Kovalev is looking to fight Beterbiev next which is a top matchup from what I know.
You have to blame the two guys at the top ..If it's not Floyd with his obvious cherry picking its Manny with his Catch weight BS .. Both guys have lead by example and now the sport will follow suit.. From Brook to GGG they are all taking a page of the book of Water! The sport has been watered down all in the name of the all mighty dollar !! This has always been prize fighting but thank God that there is boxers like Kovalev . If More fighters had his attitude these days boxing would be filled with stars again and we would be discussing the epic fights we just watched as opposed to complaining about all the nonsense that kills the sport. Cherry picking would never be able to thrive in an environment like that.