Although it seems like they only hold 'w,' their ability to trade and combine utility is what has given them a lot of success throughout the playoffs.
It seems like they have "zero fundamentals" but in reality, it's unorthodox in comparison to other teams because most teams play slow. I think the benefit of PRX's playstyle is that they barely leave it until the last 30 seconds to initiate a site. Instead, they attack sites very fast because it provides them with an advantage in numbers when initiating a site before the defending team can rotate. Usually, when a team initiates a site within the last 30 seconds, the defending side can predict the site the attacking team will hit, meaning they will be able to rotate quicker and have more numbers in preparation.
On PRX's defensive side (on Split), most of the time there were 4 players on one site because of how much space they were able to take. As a result, they only lost one round on defense. What makes PRX (on defense) even more amazing is that they barely blunder when they are aggressive. The players that usually get aggressive are the duelist because of the abilities to get a pick and then get out (for example you have the Jett dash, Reyna dismiss, and Raze satchels). The other PRX players won't get as aggressive as Jing or Forsaken because their utility is far too important to lose at the beginning of the round (especially on defense).
To conclude, teams will continuously have a hard time countering PRX's playstyle because of PRX's ability to trade and combine utility to initiate a site. There is more to PRX than we assume.
Let me know what you think :)