It could have the opposite effect. The Switch Pro will still be less powerful than a PS4/XBO. Direct comparisons to PS5/Scarlett are not going to be favorable for Switch Pro.
They aren't really competing for those graphics loving gamers, though. And haven't since the Gamecube failed. Yeah, they'd like to get some of that crowed to ALSO buy a Switch, but they know they aren't going to get many Sony/MS fans/graphics lovers to buy one INSTEAD of a next gen Playstation or Xbox.
The hope with having a pro next year would really be two fold:
1. Maybe a good chunk of their fanbase that plays Nintendo first and the others second will decide to put off a next gen console and upgrade their Switch first. That would help keep their sales and profits up during the next gen transition while they remain off cycle.
2. Have a bit more power so they still get some down ports like they have with Doom, Wolfenstein etc. that will be harder on the base Switch once devs are targeting next gen consoles as their lead platforms.