Apparently, this guy ruins franchises

Yes he does, his films are nothing more than mystery boxes with nothing in it.

He ruins them in that he removes anything that made them special and uses them to make empty vapid effects-driven action schlock. In a way he kills the spirit of the thing and all you have left is this glittery zombie that appeals to audiences of disposable flicks half paid attention to. They make money at the expense of the legacy of the original works. In most cases the original fanbase is left with mixed feelings of betrayal and then apathy toward a franchise for which they were once excited. He's not the only one who does this; a lot of franchises have gotten hijacked lately. He just does it so often and so predictably that he personifies the bigger problem.

"He then brought back Star Trek, that was pretty much dead at the time, with a movie that was well received and considered one of the best in the series. "

bwahahahahahahahahahaha

Sorry, but the "Kelvin" Star Trek is crap. Only people with total disregard for Gene Rodenberry's vision and short attention span wanted Star Trek to become a stupid ego driven action sci-fi like J.J Trek. His "success" was also directly responsible for the crappy "Discovery" TV series we got as well. And Star Wars sequels would have made tons of money anyway, even if Bozzo the Clown was directing them, because the hype was over the top. Hell, even "The Last Jedi" with Luke milking animal titties made a ton of money.