Keep in mind in RB japanese planes are grossly overtiered because it has a significant new player count who are yet unfamiliar with the concept of dictating engagements and cannot effectively use their speed well and constantly fall for “Don’t turnfight the zero.”
In addition, we have some people who call proper WW2 air tactics “toxic” that are the bread and butter of fighting superior agility aircraft: Disengage, gain separation and energy advantage and re-engage without over-committing. In another thread I’ve had a prolonged argument with someone who calls stealth and “running away” cowardly and toxic.
And finally, the arcadification of Air RB (match length reduced to 25 minutes, maps ruined to concentrate everyone in the middle rather than spread out to dilute furballs, also people who aren’t enthusiastic about propeller combat complaining loudly “it’s boring” to do proper tactics and climbing and engagements) favour a turnfighting plane that goes in and fights continuously over one that disengages, flies away for about 1-2 minutes, re-engages and disengages again.
So, this makes zeros seemingly overperform on average against average playerbase, where that average is heavily impacted by the fact that the nation most vulnerable to zeros (requires strict engagement discipline, understanding of what engagements to take and how to get a good engagement) is also the most popular due to demographics, movies and simple rule of cool.
Compare RB BRs to air sim BRs - american planes go up by 0.3 to even 1.0 and japanese aircraft as a rule go down by 0.3 or even 0.7. Generally, turnfighters get downtiered and speed demons get bumped up (thus: F4U-4 is 5.3, P-51D-5 is 5.0, P-51C-10 is 4.0, F6F-5 is 3.7, A6M3 is 3.7, A6M2 is 3.3 as examples).
Now, SB does have different conditions (ergonomics, visibility is important due to cockpit view; match duration is up to 3 hours so flying american planes properly is easier as you don’t need to worry about a 25 minute timer and there’s no markers making BnZ much more reliable even against lone targets).
Even still - with japan’s opposition shifted upwards as a rule and japan shifted downwards as a rule; facing an a6m2 zero on a rare day italy is on america’s side or japan is on america’s side in a 2.3 italian prop did not feel oppressive at all to me.