I can understand Boris's viewpoint: why bother Brexiting only to remain a rule taker afterwards.
I understand the EU position, in protecting the Single Market.
But why risk invoking tariffs immediately, when they might be invoked later, and only if UK diverges by reducing regulations? (Which it has telegraphed its intention to do so).
More importantly, it's OK for PMs to be principled, but when their principles destroy so much business and cause so much unemployment, with all the associated misery that goes with it, what use is the principle?
Additionally, the ones cherishing those principles, even if they are unemployed themselves within months, they can retire on fat pensions and the misery they have caused will not affect them in the least, neither financially, morally or emotionally.
Most importantly, the current PM is chasing his dream, not the current will of the people. One can argue that his mandate has been proven by his recent political success in the election, but where is the deal that he (and others) promised?