Joc is having literally the best offensive season of his career by a significant margin. He has had an OPS below .800 for 5 out of the last 7 seasons, though there was an .874 season mixed in there and this year he is OPSing .930.
An upgrade over Young? Certainly. The transformative slugger the Nationals need? Not in my opinion.
I think you're looking at Joc Pederson wrong. First off, he's not replacing Young. He has been exclusively a DH this year, and last year played a total of 208 innings at a position. So he's not replacing Young.
Second, Pederson is a platoon bat and has fully embraced this role. In that role, he is thriving. He's a career .246/.350/.495 against RHP, and from 2021-2023, he's hitting .250/.335/.470 against RHP. And this season, he's hitting as well away from Arizona as he is at home. The statcast data is even more promising. Even though last year was his only non- .800 OPS season in the last three, he still had xSLG of .481 (compared to an actual slugging percentage of .418). Clearing being in San Fran had an effect on him. The last three seasons, with the away stats, he's OPSing .881 against RHP.
The concern is that he will be 33 next year, but that seems somewhat mitigated by him being in the 74th percentile in bat speed. There will be a drop off with age, but there will be with any free agent we get. Essentially, Joc Pederson's average season is the best season that Jesse Winker's had in 3 years. Maybe he's not transformative, but I don't think anyone has suggested that. we're simply looking to get good production out of the DH spot and add power to the lineup. Which Pederson appears to be able to provide. I also like the fact that he is a two time World Series champion and would bring veteran prescence and clubhouse vibes to a young team.