Me and my wife watched Genysis on Hulu the other day, and I actually enjoyed it. It was stupid and absurd, but pretty fun. With most of these long running series reboots/sequels, they won't ever match the magic of the originals, but that doesn't mean they can't be enjoyed for what they are; stupid cash-ins. While I would certainly love to see an entry in a series show some real love and passion for its predecessors (ie, Creed, The Force Awakens), most of the sequels/reboots aren't going to have that.
Genysis wasn't a train wreck piece of garbage. It was just a standard action movie with Terminator pieces slapped onto it. As much as I adore the series (mainly T2, to be honest), I don't personally get offended when a new entry is mediocre. I just hope the next one is better.