"Every generation, blames the one before, " - The Living Years - Mike and the Mechanics.
The reality is that opportunities to make real change don't come along that often and you need to use them. They are not on Facebook and Twitter. Brexit and Trump were both elections. All "young" people had to do was not drink so much the night before, put down the selfie stick, get out of bed, and vote. They weren't even compulsory elections and probably only a few votes were needed. Pretty easy to move a result one way or the other really.
The "problem" with "oldies" is that they actually believe that they should vote, so they do.
The vote on the EU was a referendum, not an election, based on an incredible amount of false evidence and lying. The outcome is very unlikely to bear much resemblance to the promises made at the time and it's hard to see how the result won't be a poorer, more insular country. But then demagogues love a captive audience, the more unhappy the better. It's always all about them, their power, their wealth, never about what's actually best for people. How many problems is building a wall between Mexico and the US actually going to solve? Easy to say Build the Wall and sounds good on the tongue, though.
Anyway, it's demographics. The profile of the party in power here is almost entirely confined to elderly voters. They have hardly any support among the under 45s. Time will do for it, and for the oldies who've sold out the young. At that stage, maybe in a decade when enough of them have died off, good sense and willingness to engage with the world as it actually is may return. The sooner these destructive ideologues of any political stripe currently at play here, in the US and elsewhere are sent off with a red-hot poker up the fundament the better.