It’s hard to take seriously anyone saying candidate quality wasn’t really the main reason of the 2022 results.
Why did Laxalt and Fung lose then?
Laxalt wasn't actually a good candidate; he just looked good in comparison to Walker, Oz, Masters, etc.
Fung was running in a Democratic district. When a candidate holds a district that their party's presidential nominee won by 14 points two years earlier, that doesn't require any sort of special explanation regardless of national environment.
And Fung still came a lot closer than other challengers in districts that were comparably blue.