It surprises me they have different 'lines' for basic finishing of body shells. I know other details vary but they tend to be 'bolt on'. Having different paint processes seems odd.
I'm sure it would. Then many other things have changed over the years- gone are the days of 6000 mile/6mth services, even frequent changing of spark plugs. As for warranties, 5 years is all but standard as a min, with 7 on some.