I disagree. The forum relates to some 'thing' that exists regardless of the posters or the name its given, just as volcanoes et al. do. OK they might alter the NAME, so NOISE attaches to heavy metal, or Baroque music, but there would still be a sound phenomena that was once called noise.
So a carpentry forum would consist of posters into wood work... they may decide - or some newcomers that in fact aluminium is better and use the term 'carpentry' to denote metalwork using aluminium, but there would still be a thing - which once was called carpentry.
And both noise and carpentry have attributes... OK so say chainsaw sculpture might be a fringe activity... and some here are more into industrial and PE. But hardcore noise remains. And whatever you call it, if enough noiseguide posters decide to attach noise to violin concertos, then the noise of The Rita, Merzbow etc would require another name. However noise has other non musical definitions - SNR etc. Clipping... unwanted distortion and feedback, whitenoise, which share much of the phenomena of noise 'music'. So the name is apt.