You could apply the same logic the other way round: and reversely, British made goods will be more expensive and the continentals will simply pay a little more.
Nobody wins in restricting trade. The EU is more worried about losing face than economic consequences for their members.
So lets look at your point.
UK goods going to be more expensive in the EU, so either
a) the EU customers will buy from an EU supplier, so the UK business will loose out.
or
b) the UK supplier will think their EU market is bigger than the UK market and will move to the EU, and simply sell back into the UK, as the better option.
Conversely
EU goods, that will be more expensive in the UK.
what are the UK consumers options?
Hope that the UK negiotiates a better trade deal with the rest of the world as a small market than the EU did as a large market?
I don't see how you can think we hold any cards on trade.