That’s fine - as quoted earlier in the thread - if vendors are prepared to sell to the UK. That boutique bass guitar brand may not be available through the likes of The Gallery or Bass Direct any longer.
These additional shops you talk of are going to be larger than the small independents... and will ultimately put the latter out of business. Rich will get richer. The poor will be just be thankful for a job.
It certainly doesn’t put the EU on a level playing field. The previous deals with the UK with non EU countries were on the basis of the UK being in the EU. When the UK does stupid tricks like making vendors collect VAT on the UKs behalf, well that makes the UK a pain in the backside to deal with. Check back through the thread for the explanations.