Yup before Reagan the Dems used to have 270 -280 seats in the house and by the end of the decade he reduced that to Dems being in the 250s.
Democrats regularly held House majorities between 240 - 260 before Reagan. What you're probably referencing is those 6 years prior to Reagan where Democrats held inflated Watergate majorities. Look at the period between 1958 - 1974. The handful of times Democrats got above 270, it was due to large waves.
https://en.wikipedia.org/wiki/Party_divisions_of_United_States_CongressesWhat you are saying is true, but it was not a simple case of a crappy president. There are a lot of factors that contributed to this. Some of those he couldn't help.
