A lot..? how many is a lot? I think you'll find that the term producer goes far beyond people who make beats to sell on-line, and the definition of 'artist' includes a huge number of people who don't buy beats on-line. There's a difference between explaining why something happens and it being something good.
because they are selling beats online
I know exactly why people do it. Making beats (whatever that means...) louder mean that they demand more attention and therefore are more likely to sell. That's perfectly valid reasoning. But, it has
nothing to do with making good music. What's even worse is that the impression that it should be the case reinforces the impression that it should be the case. I think you'll find your man Bob sides with me on this one.
Further the loudness war is mostly inspired by things like MP3 players and car stereos being crap and running in crap conditions, not because of venue sounds systems.
Venue sound systems will often pay money for better systems that can make things louder by linear amplification. So if these beats are aimed at artists that intend to use them in
a venue setting, or to be used in a live/non-live production they should want uncompromised sounds, not brick wall squashed crap. If they just want to play stuff out in
a venue then they should get a better sound system if they want louder. Even if all they want to do is put vocals on top, they should demand uncompressed sounds with enough dynamic range to play with. So really, who are the people who need to seek advice about dynamics? Some random producer or someone who just wants to play sounds they've bought on-line?
NB: Soon this will all be moot as the industry seems to be moving towards standardising levels of average volume, so pretty soon all those beats (whatever they are) will sound like garbage compared to tracks from decades ago.