I play a lot of Tarkov, so gear isn't really an issue. If I die, it's not too big of a deal. Often times I'll find myself in a situation where me and the enemy both know about each others positions. I've bound f1 to be "Hold Fire" and f2 to be "Knives Only". f3 is "Follow Me".
I'll spam f1 and f2 and if I hear a response, I'll pull out my melee weapon so the other person has no fear of me. I'll start swinging it in the air so they can hear the woosh sound.
Honestly like 75% of the time, it works. People are pretty chill in this game! I find that the more geared a player is, the more likely for them to not betray me.
I was just in a raid where I killed like 5 of Gluhar's guards, there were a couple left, including Gluhar himself. There was also clearly another player as I was hearing more gunfire in the building. I did my thing, he spammed it too, he pulled melee when I said knives only, and we teamed up. I had easily 700k worth of gear on me, but there was plenty on the ground so all good no need to kill me.
I ended up getting killed by gluhar after headshotting him with an m62 round, I saw his head bounce but he got me anyways. I was trying to push him because I wasn't sure of TylerD, the new pal, was aware he was in the room. Oops.
But anyways these spontaneous teamups are really awesome, especially when you both make it out alive. VOIP might make it even better, or it might just lead to more trolls and it could get to a point where nobody trusts anybody because there's too many people lying over VOIP, we'll see I guess but I think it could make the game so much more fun!