Brexit could never be driven by Northern Ireland. And the Northern Ireland issue would never be resolved on paper by EU negotiators on the Trade Agreement demanding their rights. It had to be a pragmatic solution, and the EU are beginning to see that a hard line, purists, punishment type approach will not work. As in most issues involving NI, it will take time to resolve. In the meantime, the rest of the UK get on with what the majority of the electorate voted for. Boris delivered it. May wanted an unworkable compromise that pleased no one, apart from possibly the EU.
I don't really have the inclination to talk about the ins and outs of Brexit as we'll never agree so it's a pointless waste of time. I am, however, making a very simple point that Boris broke his promise in a way that May did not. You might think that's justified, which is entirely your right, but that doesn't obfuscate that he broke his word, as he always does.