Quite right!
In fact being from the east coast (upstate NY’er) I actually mentioned that fact about the Appalachians to my next door neighbor.
And the way the Hudson river in NY was formed by collision, a collision of a mini-continent New England into New York.
Yeah there are two main mountain builders, the collision of two plates like was the case with the Appalachians and Himalayas or the uplift and volcanics of a subduction zone like the Cascades and Andes.