Search youtube for laserface and gareth emery. The sea of phones are all recording the stage. So they are the same color as the show. They turn the otherewise dark audience into a reflection, adding to the effect. This is not a bad thing.
As for dancing, dancing is for clubs. Clubs are not concert halls. You dance at a club. You watch a show at a hall. Only DJ-types who are confused about whether they are record-spinning robots or stars in a spotlight cannot tell the difference.
I'm mostly too old to go to clubs, but to me techno and other electronic music is not about stages or visual effects, quite the opposite. Well OK, VFX can be cool.
But getting lost in music, in a darkened room with some intentionally disorienting VFX; or simply none, loud electronic music in a room with many people is already quite an experience...
that's quite different from being at a festival or at a show like this, which looks more like a musical opera performance to me.
For big room EDM, was there ever a time when it was not about laser shows etc?
I mean there's nothing wrong with stage shows, pop music and lasers.
Perhaps they could have communicated beforehand that the performance would be available for free on YouTube afterwards, so that people don’t need to record.