It's not that I want RPGs to be "po-faced", and devoid of humour. I like a bit of silly humour injected now and again, like Minsc and Boo, and I think it's generally a good practice to vary the tone, and not stay on one note. When I talk about silliness here, I'm talking about when they look at a Baldur's Gate adventure and decide:
"You know what this needs - hot rods!"
"I like it, Tim! Mad Max in hell! Awesome!"
I'm just saying that, for me, this is not awesome. A bit of well-placed levity is very welcome, but I find that a certain kind of anything-goes wackyness starts to undermine the immersion, at least for me. That's the kind of silliness I'm talking about.
Hmm, the idea of a visit by the Saints Row posse certainly has potential! But yeah; or rather no., to that idea I mean.
Also "no" to "okay Boomer". Let's not encourage that debating style.