HS2 didnt make any sense the moment it stopped connecting with HS1. At that point the London > Birmingham stretch should have been canned and a new (probably not called HS2) plan for Brimingham > north should have been devised.
None of it works if it doesn’t connect to London.
Northern Powerhouse Rail worked well – at the initial stage when it would connect various Northern cities with Leeds and Manchester where the two spurs of HS2 would terminate (with options to extend up to Scotland and, from Manchester, across into North Wales).
Then Leeds got binned so NPR instantly lost a significant chunk of its Benefit:Cost Ratio (and there’s a separate argument about why BCR is a terrible means of measuring massive and ultra-long-scale infrastructure projects anyway…).
Then Manchester got binned so NPR simply doesn’t work in any meaningful sense at all other than the north desperately needs rail investment and improvement which is now being done piecemeal.
Connection of HS2 to Euston was the least worst option given that connection to St Pancras and HS1 was near impossible. Termination at Old Oak Common is a disaster because it’ll overwhelm the already-at-capacity Elizabeth Line.
Whole thing has been an absolute shitshow overseen by a succession of Transport Ministers who have never cared in the slightest about anything other than cars