Forgive me, but I suspect many of us are not talking about the same thing. Sarcasm has a definite meaning and it most certainly is not light hearted.
A quick check of the on-line dictionary Merriam-Webster), revealed their definition of sarcasm to be…
1: “a sharp and often satirical or ironic utterance designed to cut or give pain”
2: “a mode of satirical wit depending for its effect on bitter, caustic, and often ironic language that is usually directed against an individual”.
My hard cover Collins English Dictionary defines it as follows:
“Mocking, contemptuous or ironic language intended to convey scorn or insult”.
Blue