//You cannot have Brexit without either some form of barrier between NI and the EU (ROI) or between the island of Ireland and GB.//
That is only true if you believe that there must be a barrier between the UK and the EU. There is no doubt that the EU weaponised the Irish Border issue as soon as the Brexit talks began. What has been clear from the outset is that neither the UK, Ireland nor the EU was prepared to impose such a border. We have now moved to a situation where that weaponisation has continued. We have the ridiculous situation (for example) where anything with soil attached (potted plants, used farm machinery) cannot be moved from one part of the United Kingdom to the other. It seems GB soil has become severely contaminated since January 1st (despite being perfectly agreeable for the previous 48 years and despite the UK not relaxing its sanitary regulations - with NI being subject to that same regime). Frankly the EU are extracting the urine. We should have left Ireland and their EU masters to devise and arrange whatever border controls they wished - which almost certainly would have been none.