Here's an example:
https://www.nytimes.com/2017/03/27/world/europe/aleksei-nava...
"Aleksei Navalny, Russian Opposition Leader, Receives 15-Day Sentence"
I picked this one because it generalises: the statement that Aleksei Navalny is the "Russian opposition leader" is one you can find in every mainstream media outlet: WashPo, Reuters, the Economist, the BBC, etc. But it's false. I first fact checked this statement years ago and have occasionally rechecked it since to see if things have changed, but at no point has Navalny ever held a position that could be described this way:
- He isn't coming second in any polls
- He doesn't come second in elections
- Only around a third of Russians have even heard of him
https://en.wikipedia.org/wiki/Opinion_polling_for_the_Russia...
The former communist party does better politically than Navalny.
No matter which data set you pick, Navalny is never the "leader" in it ... except western media attention, where journalists act as if there are only two politicians in Russia, Putin and this other guy.
You can find endless other examples if you start fact checking, all from supposedly reputable sources. I can't even begin to list them all because we'd never end.
I suspect your belief that the mainstream media is a bastion of truth and factual excellence is not one that will be easily shaken, so you believe whatever you want to believe. But I've given you an example, as you asked.