The Breda 501 has 8 crew members, not 5. Could you fix it this way:
Full gunnery crews are generally excluded when they can’t figure out a way to include all crew members, without interfering with the traverse or something else. This affects a lot of low-rank SPAAGs, too.
Though, there are also a few vehicles that have crew they shouldn’t have – though iirc I think that’s related to some spaghetti code where they can’t assign multiple guns or something to a single crew member(?), which is why tanks like the M2 Medium have extra crew and a lot of aircraft have extra gunnery crew when a single crew member should be controlling multiple guns, instead.
In my opinion, there’s room for everyone, but if you place them correctly and do a good job… And if it really bothers them, they could at least add the crew member in the seat next to the driver, which is currently empty in the game… It’s not even the first time I’ve pointed out that there’s space next to the driver, but the developers just ignore us:
