Fashion changes over time for all kinds of reasons. Many things contribute to the reasons for people whom wear what it is what they wear...

From W.H Murray's "Rob Roy MacGregor" Chap 3 The Barefoot Years 1673-1684 page 31:

Section on Spring

"The Springs came late, for Scotland was suffering an oscillation of climate that had brought the greatest cold since the Ice Age. It reached the worst between 1550 and 1700 with a vast expansion of Arctic pack ice. The sea-temperatures off Scotland in Winter slumped to 3°C (5° below present).

copyright is from 1982
Not saying this is the reason for the belted plaid, but I'm sure it is a major contribution to the use.