I do not believe the kind of mentality that you can make anything out of any situation with your mindset or things like that, for example that idea that if you are just super positive and hard working life will just give you sunshine and rainbows. Sometimes you are dealt a very bad hand and you can't win the game. It's more like the quote "what doesn't kill you makes you wish it did" However, the quote in post from OP doesn't imply that you can just wield any circumstance your way. It just says that you only have control over how you react to it, which is true. Example: I got laid off at my job last week. I felt upset and very sad. My instinct reaction is to go retreat in my shell and not do any of my responsibilities because I feel depressed, sad and angry. But that will only give me more shit in the future. Instead I went to my other job, met friends, and tried to find some silver lining and make the best of it.

Yes this quote can be used in a toxic positivity kind of mindset but it's also almost always in your best interest to make the best out of your situation, even if it's shitty.