No, you're still right.

The US has had two major parties for the entirety of its existence. Occasionally one of those two parties collapses and is replaced by another one, but even during these upsets it is always one of the old major parties (the one that didn't collapse) that has their candidate elected.

Furthermore, if you take every third party + every independent and combine all their congressional seats the most they've ever held was 36, and that was in 1833-1835.

https://en.wikipedia.org/wiki/United_States_presidential_election#Popular_vote_results

https://en.m.wikipedia.org/wiki/Party_divisions_of_United_States_Congresses