They are, and even more recently the growth is huge. Compare a mark 1 Cortina with today's equivalent Mondeo, the increased width and length is astonishing. Even the motor magazines say the Mondeo might cause parking problems, something that could never be said of those little Cortinas.
Another factor is that truck and bus width was increased from 7' 6" to 8' round about the late fifties, a change that took a decade or two to fully filter through into new designs and replace the old stock.
And of course, today's side mirrors on cars are monsters compared with the little wing mirrors they used to have, widening most cars by 8 to 10 inches overall beyond their body width.
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