you're right, i should of said these are CAN BE SOME of the reasons. there's plenty already mentioned. another could be is it's niche orientated music, people can find some of the music here in much bigger platforms or popular sites. some sites have bigger connections and resources to push their stuff out and expand to do more than be a forum. if you want to connect with artists, there's other platforms to use now like snapchat, instagram, facebook and twitter. although as already stated, being able to connect with artist to fans isn't always a good thing since both sides can be major douchebags.
i used to be part of a site that pushed a certain niche and i saw how difficult and EXPENSIVE it is to keep things running. eventually everyone involved who was actually dedicated to it had to move on and whomever took over wasn't so professional or had heart into it to keep it alive.
either way, it's just a rap forum to me so it's no sweat off my balls but regardless, this site still exists and it may not be as active as before but it still runs despite of it.