It isn’t intended for open field use - the BMP-T is intended to be a tank escort vehicle, specifically for urban warfare in built up areas. The AA missiles are intended for use against helicopters maneuvering around high-rises and apartment towers and such, as are the autocannons. The autocannons are also for use against high angle threats, such as ambushes firing down at the tanks from building rooftops - threats that tanks can’t elevate any of their guns high enough to deal with. It comes from the Russian experiences in the first and second Chechen War, and elsewhere. It is rather a specialist vehicle.
Years ago the US Navy operated a captured BMP type chassis with a radar dish attached to it in the high desert near Fallon. Got up next to it one day and was struck by two things. 1) How big they really are. 2) How poor the workmanship was that went into them.