Back in halo 5 the classic radar was a big issue. The devs knew this early on because they made it really small to counter act the problems and eventually replaced it with an ability tracking radar. The problems in 5 were that the classic radar made everyone aware of each other and there was not much stopping a team rushing another team. this meant matchmaking had to be perfect which is impossible.
In classic halo and infinite there are counters to a team rushing another player/smaller group. You could set a grenade trap or quickly kill someone with a melee combo so that there was at least a trade. This is what the thruster in halo 5 broke because you could always extend your life and dodge a grenade or melee and simply use team rushing to win matches. When everyone respects each others space because its a challenge to breach it, thats when halo is halo.
Sure classic halo is still different with or without a radar but both are still fun. Radar was a big reason i got into halo as its fun to use and also why matchmaking worked for a complex teamshooter like halo
Anyway, this is just me saying lets have bigger radars for more chilled matches in halo infinite.