How is every team losing to each other in Group A it feels so chaotic
Because they have 1 week between each game, so teams can prepare. That is the thing with this 1 game per week system. People have bunch of time to prepare and a lot of times the losers use more time preparing for next game and see their mistakes etc. That is why its pretty hard to stay undefeated in this system and doing so shows that you are truly good team IMO.
every team in that bracket are really close to each other interms of strats and how good they are and since there isnt a team with a clear advantage like firepower or innovative strats, its a lot more hectic ANDDD also they are given a weeks worth of time to either improve on their playstyle or to counterstrat and most teams opt for counterstrating which leads to even more chaos (take a look at 100t vs xset, 100t hard read them almost every single round) and most of these teams are inconsistent thats why teams like ghost and nrg have high reputation (pros on twitter calling them the "next optic") but fail to deliver when it matters, just give them some more time and we will see who actually is the better team