I suspect current shortages are more to do with temporary conditions such as weather and harvests. Over the last decades, we've become spoilt and expect everything to be available all through the year. I can take that in my stride.
I'm more concerned about the long-term effects of the UK increasing American food imports. HFCS and chlorinated chicken are just two examples. UK manufacturers will have to lower their own standards to compete on price. It's all very well saying that people can choose what they buy, but how many people know what HFCS is and that it's in so many American food products, eg. yoghurt, coleslaw, croutons, etc etc, not just fizzy drinks and biscuits. The Americans eat nearly 100 times the amount we eat.
Fructose is implicated in the rise in rates of obesity and Type 2 diabetes, because it doesn't stimulate insulin production in the same way other sugars do. Obviously natural fruit contains fructose, but HFCS doesn't have the nutrients of fruit and it's mainly "hidden", so people don't know they're eating it. It's much cheaper than sugar, so it brings costs down, which is why the less affluent are attracted to it.