Sorry, but you are missing the point...You think wrong. I am not missing the point.
Having different internal and external standards will increase the amount of bureaucracy in the UK and the the EU. Your example will also result in increased manufacturing costs to support different standards.
One of the prices of being free to diverge from the EU (or ‘independence’ - as you call it) is that there will be additional bureaucracy.
.... and misunderstanding manufacturers.
If the UK Govt allows different product standards for goods sold in the UK, where is the "extra bureaucracy" ?
UK Regs only have to add a line about permitting stuff "in conformity with EU standards"
Why is there an impact on EU bureaucracy if the UK permitted some extra stuff - for domestic consumption - to a different Standard ?
UK exporters to the EU still have to comply with existing EU Regs - so no change.
Why would a manufacturer experience "increased costs" - unless the UK introduced a new, UK only Regulation ?
(My assumption was based on new Regs being more permissive, not restrictive.)
And supposing there was one product (maybe an unsafe Chinese variant that somehow slipped through existing UK and EU Regs), public opinion might think any "cost" was worth it.
This seems close to WK's argument ... the logical conclusion being that there should be just one model of everything.The greater the divergence, the higher the price.
Manufacturers already make variants - for different price points - or for different consumer preferences - or for different jurisdictions.
They choose.
Look at the next lawn mower you buy.
The Handbook may well have sections for different jurisdictions.
My Honda engine appears to require different safety stickers for each of the USA, Canada, EU and "Others".
Maybe there is one part more or less. I don't know.
But Honda will make whatever variants it chooses (while being compliant).