I don't like the term 'post-truth' for a variety of reasons. But I completely agree that technology is fast reaching the point where the appearance of something (eg. A news source) is a useless way of judging it's veracity.
The biggest issue related to that is just how many people now consume news via either aggregation services or other non-primary sources.
A well-faked piece of news in the right place will get aggregated, and will get passed on by Facebook, by podcasts, by lots of secondary sources.
And you then have people saying 'it MUST be true...my newsfeed is blowing up'.
Find trustworthy sources you generally don't align yourself to. It's increasingly important.
I don't think that's all quite accurate. There are news sources and there are news sources, after all. And with experience, we come to learn which ones tend to provide real information, backed up by carefully vetted sources. Not perfect, but it's something. I've been reading papers all my 74 years, and I can tell you which journalists I trust and which I don't.
There are reliable sources and unreliable sources -- and you can work out which is which:
1. Reliable sources have links to verifiable, current evidence, unreliable sources do not.
2. Reliable sources use language that is clear of bias, unreliable sources do not.
3. Reliable sources mention the author’s name and information, unreliable sources do not.
4. Reliable sources have clear motives, unreliable sources do not, or have discernable hidden motives.
5. Reliable sources are written with professionalism, unreliable sources are not. They are reviewed before they are published, so if you see grammar and spelling errors, bet against reliability.