My personal sign is when you start seeing awkward collaborations start cropping up. One time when I was thrifting, I picked up a graphic novel that had the Justice League, team with the Power Rangers of all things. I glimpsed into what the plot was about out of morbid curiosity and it was just a plain generic time and dimension thing.
Nothing ever connected between the teams at all. DC Comics, while fledgling at times with how they go about their series and movies, still have far more relevance than Power Rangers do. I think the Power Rangers are just grasping at straws to keep being relevant when people have largely moved on from them.
I remember watching early Lost promo videos where a very smug JJ Abrams swore blind there was a fully logical explanation for everything happening. And then a polar bear showed up. And I realised that whatever definition of “fully logical explanation” he was using probably didn’t align with my own definitions of those words lol. That show was pure hype with talented actors.