Alright. Deadline is a "titan of the industry "bible. They wrote an article this year calling the "world's greatest actor" a toss-up between Denzel and DDL
http://deadline.com/2017/06/daniel-...oward-phil-lord-chrisopher-miller-1202121504/
Esquire this year declaring Denzel the greatest living American actor (I know DDL isn't American, but it sort of suggests parity)
http://www.esquire.com/entertainment/movies/g3518/best-denzel-washington-movies/?src=socialflowFB
AwardsDaily (another respected industry site) calling Denzel "the world's greatest living actor" earlier this year. I presume that includes DDL (who is also mentioned in the article). DDL isn't even retired yet and some "discerning" industry opinion seems to be shifting towards Denzel. His work in Fences seemed to be a turning point for some.
http://www.awardsdaily.com/2017/07/31/early-oscar-predictions-frontrunners-challengers/
I don't think you can rely on the Oscars to keep DDL's rep elevated over Denzel either. Denzel already has more nominations (7>5) and will get more. And he nearly won a 3rd Best Actor Oscar with Fences last year, and only a fool would bet against him winning a 3rd. So in all probability, he'll match DDL in Oscar wins, and far exceed him in nominations (if DDL sticks to his promise and stays retired).
They've got similar levels of acclaim as film actors anyway, and Denzel's status as a Tony award winning stage actor means DDL doesn't come close to his acclaim in theatre. It's not as much of a leap as you seem to believe that Denzel''s rep as the greater actor will eventually overwhelm DDL's.