in my long presence on blockland (and long presence in the deathmatching scene) i've picked up a thing or two about spawnkilling and what i like to call "spawndying"
the most obvious thing is that there IS A DIFFERENCE, FOR THE LOVE OF GOD
the biggest differentiation between the two is that spawndying is generally avoidable if it weren't for the fact that the players in question are utterly awful at deathmatching and could do with some assistance, while spawnkilling is an obvious conclusion to bad mapmaking and isn't so much something to start crying about as it is to just get up and leave like a normal person
here's an example
let's say map A is a team deathmatch that involves two fortresses and one internal spawnroom per fortress, with each spawn room only having one exit, and map B is a team deathmatch with a similar layout but with either multiple spawnrooms (with multiple exits) or alternately 1 spawn room with alternate routes to leave
if one were to die repeatedly as you leave the spawn room in map A, you could legitimately call it spawnkilling (and probably complain to the guy who built it) because there's no way around it: blocklanders will always eventually force the opposing team into their spawn once they have sufficient power to do so.
many other games have a similar problem but blockland is for the most part unique in that we can FIX our spawnkilling problems by simply editing our maps a bit: doesn't take alot of time or alot of effort, just punch a few new holes in your spawnroom and/ or fort and try to make it look like it's always been there. worst comes to worst, maybe you have to carve out or expand a bit on your old map, but that's usually not as bad as such a big weakness as one team being entirely unable to do anything while the other team gloats hysterically at the fact that their opponent can't score a single hit without getting shot into swiss cheese
on the other hand if you were to die repeatedly as soon as you leave the spawn in map B, you probably couldn't call it spawnkilling unless one team vastly outNUMBERS (not overPOWERS which implies one team either has better firepower or better players) the other team: this phenomenon i call spawnDYING and is almost always due to teamstacking and can easily be fixed with a quick /sortplayers
it's also spawndying if the players in question repeatedly walk into the same scenario mindlessly and tactlessly with no forethought and hope for someone on the other team to either slip up or for fate to just happen to twist in their favor or something (which incidentally is a symptom of insanity)
tl;dr
blocklanders are like lemmings
they will constantly do the stupidest goddamn things and then cry when it doesn't work
please make your deathmatches in a way that accounts for this