I tend not to engage in this perennial debate, mainly because its terms lack precise definition. Hats off to ParrotHead for articulating as good (and narrow) a definition of "spawnkilling" as we're likely to see. But based on the in-game howls of protest I've been seeing lately, a lot of people define it way more broadly, more like, "being shot down anywhere within fifty plane lengths of the respawn point." LOL !
But even ParrotHead's definition is problematic. Define "off the ground" for example.
Then explain how I'm supposed to tell whether any given plane is "off the ground" or not in that thicket of respawning planes all of which to my aging eyes squinting at this tiny phone screen look smaller than a gnat's arse as I'm hurtling toward said thicket while laden with a bomb and dodging bullets from all directions!
LOL! While you're at it, tell me how many angels can fit on the head of a pin!
Anyway, for the record, I am firmly agnostic on the issue. Which means I'm a card-carrying Dentonian.
But hell yes I will indiscriminately shoot first into any oncoming bullet-emitting cloud of red gnat-arses while bringin it with a bomb, and ask questions (or apologize) later.
beyond that its a judgment call based on local conditions, relative strength, numbers and experience of opposition, etc.
I take no position on the "morality" of spawnkilling. I mean, c'mon people! It's a game! Life's too short to get too worked up over it. And as to whether or not it "discourages" new players, I have no idea. I just know it never discouraged me, and I've been spawnkilled countless times by countless players of all ranks and at every level.
But I consider it a badge of honor from artists like Bomber and Enzo.