@shtupurgnamakitin game since 03.2021, hit D4 in my 3rd split? and been there even since.
Can you do it without a set squad - yes, BUT you have turn off public style play (as mentioned in the previous comments you can't push everyone, rush, make many incorrect decisions), in many cases you need to give up on getting up your teammates or their banners and favor placement points = camp, avoid enemies as long as you can. Be ready for 20+ min games where you get +4 RP and no kills (well with the new system probably math will change and you will get even fewer points for 0 KP games).
With at least 1 regular and similarly skilled player for me getting Diamond 4 was easy, we literally won every 5th game or so.
Diamond+ lobbies = pain, suffering, hacker paradise.
The biggest change for me was hackers.
I knew the basics and my playstyle was far from the public so that was not an issue, I was used to slow phase, low KP games and that does not trigger me.
Hackers - another story.
You see ppl all day long in every lobby who pretend to be really good at the game, some of them are, but most of them are just plain hackers or very good hackers (even worse).
No recoil in my opinion is almost a must for all who get there, that's what you will see spectating your killers, most of them will have dead-on steady crosshair no matter the gun or distance.
Another thing you need to understand is that Diamond lobbies basically is cannonball meat for Masters and Predators (due to their numbers) = Matchmaking pushes weaker Diamond level players into Masters and Predators rather than add lower-ranked Platinum4-1 players into Diamond lobbies. So you as a first time Diamond can just bet that every fight you take is not even close to 50/50, more like you are lucky if it is 40/60 or 30/70, most of the time I kept dying like back in the days when I started the game - you just have no clue how they killed you so fast and you missed all of your shots.
The last weeks of each split are nightmare hacking wise - ppl boost wannabes who will do anything for a badge and trail, so e.g. last week a day where I play 5 games and in 4 I get eliminated by a hacker was no surprise, instead of playing ~50 games per day like I used to, I limited myself to <10, because it is just pointless.
Finally, room for error in Diamond is pretty much zero:
- you get broken - most of the time enemy team will just jumpad/rush you
- you get knocked - 100% of a time enemy team will push you
- you don't shoot at the enemy squad constantly e.g. relocate during the fight or all team heals at the same time - you will get pushed 100% of a time
- you miss 50% of your shots - you are dead
- ppl get to you close range - will probably 3 shot you from Eva or Wingman or land a whole mag from an automatic weapon
- you fight longer than ~1 min - you will get 3rd partied 100% of a time
- you miss rotation and go through choke - you will be met by a team camping it
- you think that enemy should come from point A - they will, most of them will at the worst possible time for you thanks to the fact that many use wallhack to see what is going and time their attacks perfectly
- etc.
My suggestion - get do Diamond 4, by that time preferably get 2 people who are ready for the pain and grind, do your best, see how it goes. If you are similar to me and just see no point = quit ranked or the game until Respawn takes care of hackers aka pro aka players who train aka players who know rotations and any other marketing therm you will hear along the way when accusing not 100% clear hackers that just plainly aimbot.
