I figured I would just respond to both of these quotes. It seems like the microbreweries and that demographic definitely aren't your place. Your band, based on what you've described, and these locations/demos just seem to be two different worlds. For example, the rock and disco especially seem very out of place for that demographic. On average, the younger person just doesn't want to see a bunch of old guys playing old songs that they (the younger audience) doesn't care about or have any connection to. Are there any other locations you can play that might be more fitting, where you will be better appreciated?
As a 20 something, I've heard and read that "don't know how to react to real life" stuff a lot, and trust me I know it's at least partly in jest, but there is still a huge scene of 20s people going out in general and socializing, as well as going to see music. It's just not the same music anymore/the music you are playing. That is in one sense a type of rebellion that is indeed happening amongst younger people. They simply do not want to go out to see cover bands of guys playing the same songs they've been playing for 40ish years. And there is plenty of both mellow and non-mellow music in the younger demographic. Heard any modern metal variants? Anything but mellow. Things are more fragmented now than they have ever been. There's lots of stuff out there, you just have to find it.
Honestly, I see just as many people who are up into their early 60s who are as addicted to their phones/social media as any other age group. It's not just a young person thing.
I have also talked to many people these days who do not want there to be a band when they go out to a bar or out to eat. They view it as an annoyance, a distraction and a turn off and I've heard it compared to annoying trivia at places, where people will choose to go somewhere else without for their night out.
I don't mean any of this to be insulting, just in case it came off that way. I'm just trying to offer you a different perspective. I definitely understand all of your annoyances with the way things are. I hope you and your group are able to find some local places that you can play regularly that will have a more fitting, appreciative and interactive crowd for you. There's nothing worse than a wallpaper gig.
Good luck!