There has ALWAYS been bias in favour of Rangers and Celtic, certainly all of my 50 odd years as a supporter, and way beyond that too I'm reliably informed.
Everything is geared towards the success of those two clubs, not just the governing bodies and match officials but the (not to be under estimated) media coverage too. We all know this to be the case but it's more obvious now that people are highlighting and discussing incidents on social media.
Though it's far more transparent to greater numbers of people now, I do sometimes wonder if they're THAT ignorant and obsessed with their own little world, they don't even realise or care how obvious their bias is to all the rest of us.
It serves to remind us just how good we really were to achieve the success we did in the 80s', despite obstacles that certain other clubs never have to contend with.