Prepping in the 1970s meant a larder cupboard bursting at the seams with tinned food, dried milk, flour, sugar, everything you could afford, along with a mould for making fire blocks out of old newspapers, having a tin of candles and matches ready all the time, a large can of paraffin for the heaters and essentially, having as much stored as you could in case the power went off or there was another strike or shortage. And growing loads of vegetables in the back garden, along with trying to get as much from the coalman as you could and buying a padlock for the coal shed.
If you lived rurally, you also stockpiled wood, had even larger tinned and preserved food stores, swapped jams or extra vegetables from the garden without asking too many questions about the origin of various game that appeared late at night and made sure that the hens were well locked up for the evening long before it got dark. And you made sure that the range was kept in good nick, as if something went wrong in midwinter, you'd be without heat or hot water for weeks. In some places, you also had a plan for what to do in the case of floods, being snowed in as you still remembered the winter of 63, if not the earlier ones that your parents told you about, and you hoped that it would all work itself out before long, as there was no way you could do anything about it if deliveries couldn't get to the village shops.
You also had a large sewing basket for repairs, as many tools as you could get and if you were any good at knitting, you wouldn't just be making cardigans, mittens and hats for babies/your own children, you'd be able to get some extra money for knitting extra items for other people's children.
Prepping in itself isn't a bad thing - because at least those who do it aren't hysterically piling chilled pizzas, milk and loaves of bread into shopping trolleys at the first sign of snow; or bitching that there's nothing for tea because the supermarket shelves were bare.