I could take a stab.
Polls were specifically rigged to show a Democrat victory.
I suspect that's what he's referring to.
There are only a few owners of American media, and they have their agenda. This election cycle was a bit odd in that the normal right-leaning media companies were aligned with the left-leaning ones, so you got bad-mouthing of Trump all-around.
Once the right-leaning media realised they were about to put Hillary into the White House, they did an about face and started doing their normal biased reporting.
Meanwhile, the left-leaning media kept their bias strong from the start.
This seems to be playing out similarly in Great Britain, with their media taking sides, and at the moment, the left-leaning market forces are stronger. I suspect this is due to the huge benefits globalism brings to the media owners and their financial friends.
The problem is, the population at large doesn't benefit from globalism as directly and obviously as the media owners, so they're not playing along with the game anymore.
Just a guess, mind you. GP might be on about something else.