Did they predict it? They poked fun at the whole Trump-in-over-hid-head-ness, but I don't think they really intended to predict anything. They always keep possibilities open, and add finishing touches to episodes day before airing.
They announced they will back off from Politics. I think it's mostly because they would get benefits from Trump's derregulation policies and they don't want to risk it.
What's annoying is that they had so much material for both Trump and Hillary, but then made the main plot about rick rolling and "le epic trolling", whilst still having political icons as main characters. S20 was a fucking mess and I hope they go back to one-off social commentary episodes next season.
I can understand them to some extent. It's easy to insist political comentators comentate fearlessly, while we ourselves are not high profile political comentators. One thing is having al qaeda whine about decapitating you, it's hyperbolic and a one-in-a-million kind of threat. Another is losing half your viewer base. SP always prided itself on its "political neutrality", catering to everybody