i think far fewer modern cars will survive long enough to become classic manufactures are getting very good at makeing cars last for there desing life. it reported to be 5 yrs / 100,000 without magor mecanical mantance and then plug on for another 5yrs with help then fall to bits in a heap.
mk3 golfs will become much than mk2's quite quickly. as us mk2 owners like buy them to extract the good bits and as mk2's get rarer and worth more parts and restoration budgets will increase