I'm a millennial and I graduated college 20 years ago. We're in our 40's now.

Technically, I-90 in NY is "the Thruway" all the way from the Mass line to Buffalo. this side of Albany it's the "New England extension of the NYS Thruway." I-87 is also the Thruway down to NYC, and The Northway north of Albany. The L made by I-87 and I-90 and from NYC to Buffalo is all the Thruway and it's one continuous toll road. New Yorkers typically call it The Thruway instead of calling it I-90/I-87. No one calls it "The 90" or "The 87", though.

I've lived here 20 years and I've never heard anyone, at any point, call it "The 95." It's "95", "I-95", or "128."

The reason that highways in CA are prefixed with "The" is because they all had names before the interstate highway system gave them numbers. so, it's called "the 5" because it used to be called "The Golden State freeway" and "the San Diego Freeway". That would hold in MA for our named road, The Mass Pike, but here the article doesn't transfer to the number, so if you say "The 90" people will look at you like you just fell off the turnip truck.