Well, your first assumptions isn't accurate, it has been nearly two weeks since the Barr report and Trump has not received any bump in his numbers, take out the Razzy, and they sink further
https://www.realclearpolitics.com/epolls/other/president_trump_job_approval-6179.html
Ditto the fake news comment, playing the media martyr only sells on the right, and as I noted, everything indicates that Americans see the economy in spite of Trump and not because of Trump
Even the Obama "whataboutism" is weak, Trump never faced the historical recession Obama was saddled with, in fact, Obama left him an economy on the rise
And Trump winning in 2020 depends largely on the Democrat candidate and campaign that candidate accomplishes. Not saying Trump can't win, he can, difficult to beat an incumbent especially since it will come down to half dozen States, but he has to have a rival that matches Hillary's ineptness