its a set prop dude. chill out. they're not playing with children's toys like you're STILL attempting to insinuate. i don't see a problem with it, thought that was clear enough from my first post. firstly i think they're loosely re-creating their pastel dynamite outfits and the merry go round is a bit of a vintage touch bc i think they were way more common back in the day than they are now. its clearly meant to elicit a sense of youthful whimsy and might even be purposefully meant to stand in for/be a metaphor of the carnival merry go rounds, which is imagery they have used before.
idk, something about the fact that what you're essentially saying here is "they're too old too old to be doing x,y, z" doesn't sit right with me. tae literally has a song called inner child. if this is an attempt to say bh is "infantalizing" them, i just think you're missing the mark. clearly many fans like bright/soft concepts from them. dynamite and bwl are great examples of that.