I certainly agree with the point re self sufficiency. We have basically thrown away our World leading position in terms of raw materials, manufacturing, etc., and now far more reliant on importing, whether it's power, goods, services or even immigration for staffing.
Just look at the effect of a single container ship blocking the Suez canal for a couple of weeks which caused widespread shortages of all kinds of goods.
We need to urgently start to work towards self sufficiency again as far as possible. If that means we pay more and consume less, then it's a good thing, not just for the country, but for climate change. It can only be a good thing if we have to pay a few pounds more for a dress made in the UK that we can use many times rather than buy a cheap one from Primark that we're happy to chuck after being worn once. It'd help the environment if we stopped flying for a weekend hen-do to Magaluf and partied in the UK instead! Holidays abroad should be less frequent and more special. We should think more about buying stuff and be more aware of the cost, climate change impact, working conditions of the factory/sweat shop workers, etc.
It's taken decades to become over-reliant on other countries, and it will take decades to get back to being predominantly self reliant, it's hard, but that's no excuse not to make a start.
Covid showed us how reliant we are on other countries. Our import reliance meant we couldn't close/restrict our borders in the same was as other countries. We still had huge numbers of planes bringing in goods, huge numbers of "white van men" crossing the channel bringing goods, etc. In a perfect world, most of that could have been made in the UK and vastly reduced numbers of planes/vans bringing in "essentials" that we couldn't produce here.