Maybe not expressly forbidden but I've rarely seen bumper plates in these types of gyms, and some do not allow you to drop weights.
If the weight makes a noise loud enough to draw every gym goers attention, you are lifting too much and should deload. Or you just might be that guy ;)
That's not to say that you won't benefit from working with a weight where it is possible to control when lowering, but there's a lot to be said for power cleaning a higher amount and dropping upon completion of the rep.
Gyms are not libraries. They should be dirty and loud.