There was almost no advertising in my country when I was 7. I live in Poland and till 1989 it was communist puppet state of USSR (not through our choice, obviously, so the moment we could - we noped out of it).

There was no point advertising because there was no competition, all the companies were nationalized and no matter how well or badly they did - their employees earned the same. If you persuaded people to buy your washing powder instead of the other available washing powder - that just means the queues for your washing powder will be longer.

There was A LOT of communist and anti western propaganda tho. But no advertising is perfectly possible.