Not sure what are you complaining about:
- inability to be afk and yet not dead in the game
- spawnfarming in ranked
- spawnfarming in other modes
Since I have been in FPS games spawnfarming or more precisely knowing spawn places, timing has been part of the game, especially in "nothing to lose" modes like deathmatch aka pubs where basically people come to test things out, get into the competitive mood, just run and gun.
Regarding your example where people camp next to spawn place - well that is game awareness imo. I see such trends once or twice -> next time I spawn I go straight for that easy camper kill. So should the rest. The fact that it works in some games just means that people are unable to identify such trend during the game and allow such players to actually farm spawns for free.
Spawn protection has been successfully implemented in many games yet it would just alter timeframe of spawnfragging and not solve your gripe = instead of instakill on spawn players would be able to camp say around the wall or corner and do exactly the same just a few seconds later.
As for being killed while afk...man don't get me started. If you are afk:
a) you ruin the game for others
b) your own fault you could not time manage your gamer properly
Game can't be blamed for not covering for your expected or unexpected afk time.
