Honestly...does the game have to be 128 though? What about reducing sizes to 100, freeing up some CPU overhead for more map complexity and other things, and slightly larger squads of say, 5? That allows for 10 squads per-team, closer to the 8 squads per-team in 64 players than the 16 squads per-team in 128.
Fewer squads overall, a 25% increase in squad size to allow for more teamplay and slightly larger groups of friends, and slightly less players overall in the game while still staying closer to 128 vs. 64. Obviously would require revisiting the 64 player cap on smaller maps as well. But like, it seems BF2042 is critically looking at a lot of the "core" concepts in BF including classes and the 64 player size to begin with, so why not keep the questions going?
They'd still need to allow for multi-squad support so you could play with more than just a single squad worth of friends though.