This is a very, very crappy (probably even shitty) trend since it's victimizing Bowser, a villain (like basically most people in the Mario community). A lot of people treat him like either the evilest guy there is, or just a broken dude, when it can be mixed.

First, let's talk about why he's evil. He has kidnaped Peach countless of times (as well as the Toads, Luigi, etc.) and forced her to marry him even though she said no. In the movie, when Peach rejected him, he told Kamek to hurt one of the Toads. Bowser also tried to nuke the Mushroom Kingdom (movie), turned the Toads into inanimate objects (Bros. 1), destroyed the galaxy twice (Galaxy 1 and 2), committed a bunch of crimes and is overall just a bad person. You might say "Oh, well what about all the times he has helped Mario and co. (RPG:LOTSS, +Rabbids:SOH, etc.)" and it's true he has helped them before, but it was only done for his own benefits. He never actually did those things to become good, he'll only help them if he gets retreated afterwards.

Now, as to why he's broken... there aren't really any reasons as to why he's broken other than the fact that he gets rejected by Peach over and over again. But this does NOT mean we should treat him as an innocent soul. Bowser is still a villain we have today, and he doesn't want to change that.

To summarize this thing up:

Bowser is evil, and LOVES being evil, but he's also broken. Peace out.

Edit: I just saw a video of this trend saying how Peach rejected Bowser without thinking about his feelings, I'm going to fucking laugh.