Many times productions of rock music are wrongfully accused of being badly recorded and mixed, but as
@Sacha pointed out, rock and metal music is often much more challenging to mix as there is usually much more going on at the same time, as there are usually intensively played instruments that compete for the same frequency range which will unavoidable cause more frequency masking.
The big challenge to avoid some of the frequency masking is to get all the pannings right, sometimes carving out and dedicating certain frequency ranges for different instruments, and get the compression level right for certain sound objects which are usually the kick drum, the bass guitar, and the vocals, as those sound elements often have way too much dynamics to work with everything else in the mix without either getting buried or overwhelm the rest in a crowded mix.
A thing I think most listeners have noticed is that when it comes to a less dense part in an otherwise crowded and dense rock mix, a segment where just one or two of the instruments are played, the individual instruments are often pretty well recorded when heard on their own but right at the moment when all the other instruments come in, it can yet again sound way worse in a way that may make people think it’s badly recorded.
But if we go back to the topic of this thread.
Some loudspeakers just seem to be way better than others at keeping things separated when a music mix gets dense with a lot of frequency overlapping of competing sound elements, that without making a total mess out of everything keeping good separation and layering, and a sense of “calmness” of how everything sounds is somehow kept in check even when the music itself is highly dense and intense.
