Many of the same researchers that developed the techniques that Exxon relies on to find oil also developed the arguments about anthropogenic climate change. There are certainly individuals within Exxon who acknowledge climate change. I do not envy their cognitive dissonance.
I don't follow US politics very closely, so I don't know whom you are referring to; but if they were a fossil fuel CEO, they may no longer have a financial interest in quitting.
40. You need 66 to ratify a treaty, but you can also pass a 'treaty implementation bill' which is basically normal legislation mirroring the language of the treaty, and you only need a majority in the house, and either a majority or a filibuster-proof majority in the senate. That's how NAFTA was passed.
Obama could have tried that with the Paris climate deal, but now it would require Trump's signature, or enough votes to override a veto (again including 67 Senators).
But both sides seem to be playing by a new rulebook here, in which the President makes international agreements without consulting Congress.
This particular example may not demonstrate it, but it absolutely is an American issue, not a Trump issue. Denial of climate change, its negative consequences, and the merits of fighting it have been a standard part of the Republican platform for a long time.