In a way you are right, but I think games like Skywars and Eggwars are big and long-lasting enough to allow the parties.There are also big partys who farm eggwars wins on Rome and Mansion. The same goes for skywars. This would change the game alot. I think it would just be better to make maps for smaller teams. Like 3v3.
Blockwars Bridges is only played by about 60 people (at the same time) while in Skywars there are at least 600.