A lot of people don't eat the broccoli stems. Broccoli is the floret, so they just eat the pretty part. Same as how some people don't eat the skin on their potatoes because that's the dirty part.
I'd try the melon rind purely because it's different than it sounds: it's not a bowl of watermelon rind. You remove the green part and then pickle it. Given what pickling can do to change a cucumber texture I'd be open to trying it. That being said, I'm not a huge fan of pickles, so most likely it's capped at a pretty low score for me.
And that's part of why I'd push back on the culture war angle. Many of these are not things we've found distasteful since time immemorial. Roast squash seeds are sold in stores. Pickled watermelon rind is a southern food. Banana peel curry is well prexisting in southeast asia.
If you look at it from the angle that you received the broccoli stem information, but remember that each item has someone out there saying the same thing, it's a lot less solidly "normalizing eating trash" and more "clickbaity news headline - eat more fiber".