Guitar tube amps are still alive, because we have Led Zeppelin, Hendrix, Van Halen, and Slash to thank for our love affair with tube tone. Tubes are essentially defunct just about everywhere else. There's some tube hifi gear made by companies like Cary Audio and McIntosh, but they also make solid state hifi systems as well. Mainstream audio companies such as Bose, Altec Lansing, Logitech, and Klipsch will never make a tube product. There will be NO resurgence in tube technology, ever. It is only diminishing. As tubes are more expensive and less reliable than silicon, it makes no economic sense for a company to continue using tubes when there is a stronger alternative. As the Axe-Fx demonstrates, improved DSPs can get pretty damn close to tube tone. The only staying power for tubes is in our nostalgic minds, because we want to be cool like Van Halen. When that wears off with successive generations who care as much about Van Halen as I care about Elvis Presley, the love for tubes dies as well.
It comes down to this, if silicon can do what tubes do for much cheaper, with more reliability, and drastically reduced size, tubes will die. There's no question about it.