The motorbikes squad is a small, multi-purpose squad that can have all three infantry classes in the game, but it has the problem of spawning on the motorcycle far from the map; and even if it spawned at the front most of the time, it’s not suitable for all maps, so allowing them to spawn as infantry at rally points and default spawns would be a good alternative in such cases.
This would be pretty dull. APCs are capped at three per team, so that rule works for them, but there’s no such limit on this vehicle, so there’s no need to ban it.
What’s more, players might accidentally select it by mistake — intending to spawn on a motorcycle, only to end up on foot instead.
There are 3 specialized soldiers: with the engineer you build an ammunition box, sandbags and an additional rally point, with the medic you leave the medic box and wait for wounded, and with the anti-tank you defend against tanks and intercept enemy APCs, give to one a good rifle or submachine gun and you have a good defense without spending your default 3 infantry slots, especially useful for new players.
I think they should at least add a useful buff for it, cutting the required manpower down to one. Otherwise, it’s simply not worth using. A medical squad would be a much better choice instead.
As I said, it’s not suitable for all maps, especially urban areas. Once your team advances or has to retreat to a more open field, you can reappear with the motorbike.