What are good manners in the game and where is the border

Good day everyone!

I was invited to DBD by a friend a few days ago, and really liked the game (though from youtube i already understand it's too deep to learn without wasting a life, lol). I enjoyed learning as a survivor and then the time came to learn killer's perspective.

After playing my very first 15-20 games, i started getting "no fun no skill boring tunneler" messages in after game chat. Spoken to my friend, i understood that this game is very different from all other multiplayer games i have played during past 18 years - in every game bad manner means being toxic, insulting people or intentionally feeding. It was quite easy to stay a good manner player for almost 2 decades since the "do's" and "dont's" were very clear.

But DBD seems to be a COMPLETELY different story to me. From what I could understand from reading forum and watching some random youtube vids, there seem to be a complex set of "additional" rules, probably existing because the game balance is not.. perfect.

That makes me ask 2 questions.

The first one is: what are main "special" rules in DBD both for survivor and killer?

In my first ever killer game where i took out all 4, i felt happy enough and brought the last guy to exit and let him go. But I lost 2500+ points bonus for killing everyone, and i struggle to get enough points all the time, and also got 1 rank progress instead of 2 just for doing this little gesture. I guess it's important for the beginner to maximise points?

When I play as surv, i noticed a pattern. Every time i decide to play good manner, unhook others and do my best to heal them and cooperate, i get killed very fast and lose the game, getting low points. When I try to play selfish, i tend to win and escape the game. I don't want to play a solo game, but it feels so much more rewarding.

When I played killer there were often situations when i hooked someone and went to damage the gen, then returned and there was a survivor unhooking right at my face. They usually try to put their bodies between me and unhooked person, but i just step aside and make a few more steps to hit the unhooked guy. This makes perfect sense for me since it's just 1 hit to kill - against an extra hit and a long chase that may end with nothing and I just lose time and possibly the whole game. But then people call me tunneler after game. I googled about tunneling and i have very mixed feeling about it. As a survivor, I always felt devastated when being tunneled, but I also understand that i did mistakes and my allies also did mistakes to allow that happen in the first place (not safe unhooking, being bad at chases etc). Allowing a player to escape just because i have to hit someone else, making an ineffective decision because of non-official rules looks... weird, something that I never experienced in any other game.

i know already that camping sucks and only did it once to punish extremely good high rank player who made me loop for half an hour and really had to be punished for that to my opinion. Then people told me that if someone is so good i have to respect him, not punish after finally getting him down. Is it so? Should community morale codex override my own feelings and experience from the game?

You probably guessed already that my second question is:

How do you determine the border between being a fun good manner player and ineffective player that is wasting lots of bloodpoints, losing games and making slower rank progress just to look good to others? How do you balance out your reputation and outcome of the game? This applies to killer especially i guess.

The game is fun and challenging for me so far and I will be happy to find the balance and learn how to be both a good survivor and killer.