Aside from an open world, there doesn't seem much comparison or competition between Cyberpunk 2077 and Red Dead Redemption 2 - but but market analysts believe it'll be "more popular" than Rockstar's Western epic.
These analysts take it as a good sign that Red Dead Redemption 2 has sold so extremely well, and believe Cyberpunk 2077 will do even better in sales - thanks in part due to the setting and the fact that, unlike RDR2, it's launching on PC. More details are below.
This information comes from a document posted on Stockwatch.pl, a Polish stock market and investment website. While translations are never 100% accurate, self-proclaimed "native Polish speaker and translator" Dr4kun on Reddit seems to have a decent translation of a key section - which matches what we could translate ourselves.
Stockwatch states that "quality remains the absolute highest priority for CD Projekt, and Cyberpunk 2077 will be no less elaborate and polished than RDR2". They are forecasting USD $525 million in sales - whereas RDR2 (gross) was $725 million in its first three days, which they also point out is only on consoles. "With that in mind, our forecasts for CP2077 seem very reserved - remember the game will be simultaneously both on the consoles
The analysts also believe that "the world of Cyberpunk / sci-fi should be more popular among gamers than the Wild West". That remains to be seen, especially as Rockstar is in a category all of its own when it comes to videogames.
Stockwatch are changing CDP(R) stock from 'Neutral' to 'Purchase', so they're expecting big things from the company. Regardless, everyone is clearly hoping for big things from Cyberpunk 2077 when it launches, especially as the sales for both Gwent and Thronebreaker: The Witcher Tales are apparently "below the company's expectations", meaning CD Projekt RED. We're certainly eagerly anticipating Cyberpunk 2077... but will it beat Red Dead Redemption 2 when it comes to sales?
Note: A previous version of this article wrongly attributed the original document's comments to Cyberpunk 2077's developer/publisher CD Projekt RED. While a lot of this seem to be based on impressions or statements from CD Projekt, the direct quotes are from market analysts.