I disagree. The fact that kids may like a character or a property is not, in and of itself, a good reason to alter that property for children's consumption.
Kids wound up liking Robocop, for instance, but every attempt to lighten up that character for TV/more general audiences produced utter mediocrity. Some characters simply aren't served by being toned down.
If a character is designed for adults and happens to also appeal to kids, great. But that's never, IMO, a viable reason for changing the character to mesh.
Robocop never had a history that involved throwing criminals off of buildings, kid sidekicks, villains named Kite-Man who were born with the name Charles Brown, murderous clowns, a dog with a mask, Bat-Mite, murdered parents, and so on and so forth...
...all before most of us were born.
The idea that there can only be one true interpretation of Batman is ridiculous. And guess what? You can have a serious character in a show that doesn't take itself entirely serious.
And even in comics? The Batman in
Detective Comics,
Batman,
Justice League of America,
The Brave and the Bold, and
Batman Confidential all are more or less alike, yet the tone of the stories is vastly different.
The Brave and the Bold comic? At one point he merges with a cyborg, becoming half-Batman, half whatever the heck that Legion villain's name is. The character himself is essentially the same as always, but the tone of the story he's in is drastically different than the more crime-noir that is
Detective Comics - which in turn contrasts with
Batman, which while still more or less serious, plays up more of the superhero aspect of Batman in it. Oh, and right now also has Bat-Mite popping up.
It's not necessarily the character that changes, it's the tone of the story. The tone of the story can change drastically, yet the character can still stay more or less the same.
But, if it bears saying - there can also be multiple interpretations of a character at once. It doesn't take a genius not to confuse them. The Robin from the
Teen Titans cartoon is notably different than the one from the original Batman series. One doesn't take away from the other and there are still similarities between the two.
And again, to the Booster Gold and Blue Beetle happy hour (which should obviously be Booster and Jaime Reyes, of course) - no, not going to happen, not now, anyway. They're not going to draw in nearly as many people as Batman. Heck, not even Superman likely would - Batman is quite possibly the most popular superhero, period. One of the most popular characters, period - the past few popular character polls here on Enworld wound up either with Batman as the first or second most popular character after Indiana Jones.
Besides, the show we're seeing doesn't look like it's comedy - it looks like it's Action! With a capital exclamation mark. It just doesn't take itself too seriously, from all appearances. Because, really. Bunch of guys in tights and funny costumes. It's ok to acknowledge it's all a bit silly every now and again.