I don't think that is a generalisation which can easily be made. Many factors in play as well, e.g. imagine the situation where the birds normally have to be at

I don't think that is a generalisation which can easily be made. Many factors in play as well, e.g. imagine the situation where the birds normally have to be at about ground level to pick seeds, and one hangs a feeder on a washing line. The latter cannot be reached by cats, in the former situation the casts just have to wait for their possible meal to arrive. At the same time seeds drop from the feeder so birds going for that are an easier target for cats. But that's back to square one, so might not total to increased risk.