In case you forgot that this was the metric you are using as support for "historical underperformance"
And here is some more help for you so that maybe you'll get to that epiphany.
1992 - Dems control 267
2000 - R's control 221
2008 - D's control 257
2016 - R's control 241
2020 - D's control 222
Get the picture?
Lets not forget that the R's won 13 seats in 2020 but of course lost the presidency (Despite winning 19/20 bellweathers and volumes of statistical evidence showing the jump in voter participation in dense urban areas was almost impossible).