Here's my take on it.
I think the bloke has a fair point, basically. And if there is good music out there but people have stopped bothering to look for it then it accounts for the same thing anyway, that most people can't be arsed so there isn't enough enthusiasm to keep the music alive as a major force.
What I think the major problem is right now - and this applies to other genres of music as well - is that the current formats have been done to death, drained of every last drop. Sticking to dance music, the history is one of old music being rediscovered and reinterpreted using new technology or musical styles. It's predominantly black music or black-music-based white music. And all the archive has now been plundered, well and truly stripped. Looking to the technology, turntables have been done, drum machines and samplers have been done - it's all been done to death in the search to re-manipulate those old sounds and create new ones. Yes, there are new tracks coming out but it's all variations on a very tired old theme.
I don't think dance music will die. And I don't think other musical genres will die. But what they need now is one of those periodic reinvigorations which happen in music where some forgotten musical genre is rediscovered and reinterpreted. Thing is, I don't think it's going to be based on black music as that's so exhausted it's even stopped twitching now. Where it will come from I'm not sure but it will be from somewhere else.
And I also think that somewhere in the mix will come some new technology - or a discovery that existing technology can do things hitherto unrealised to create new sounds - and that will be coupled with the reinterpretations above.
One of the big barriers at the moment is that R&B and hip-hop is so big, and so many vested interests have so much money riding on a continuance of its dominance, that a break from black-based music will not have industry support. And it will take a very adventurous soul to think out-of-the-box and look to other genres for inspiration when they are being bombarded daily by the same old same old in different clothes.
Music goes through this from time to time. Things will have to move on or music in general will die out as a commercial proposition. It's that stale now even cheese smells better.