The BAe/Avro were also a little too large to be practical in the USA given the number of passengers they could carry due to mainline pilot scopes. For example, XJ
had to configure their RJ85s down to 69 seats to meet NW
's pilot scope at the time, but most of those same birds are now flying with 95 seats for WX
in Europe. Considering DL
has the most liberal scope by allowing 76-seat RJs today, that's still 19 fewer seats than the birds fly with in Europe. That's a lot of extra airplane to purchase and fly around without earning any additional revenue.