A significant number of Fokkers have gone to Jetsgo in Canada.
Such aircraft are no longer popular in the US because of union agreements called "scope clauses" which make it more efficient for US carriers to use Canadair/Embraer RJs rather than the Fokkers. (This is a gross generalisation which those closer to the situation will doubtless have a contribution to make).
Fokker 100 seating is 2+3.