The reason why "Let's scrap HS2" is gaining traction is because there are many unanswered questions
I don't know if it's gaining traction or not (I agree that HS2 is non popular but that's not the same as gaining/falling in popularity).
But I do know that in 2019, the Great British Public seem to be against large long term projects, they aren't happy with "jam tomorrow", they distrust most arms of Government and generally prefer simple short term solutions. Something like HS2 will take a decade or more to build, it has benefits that are currently unquantifiable to most people (partly because some of the twentysomethings who might be using HS2 to commute in the mid 2030s are still at primary school, whilst today's "rich businessmen" so beloved of clichés will have retired by the mid 2030s, so it's hard to see "what's in it for me" when planning so far ahead).
After best part of a decade of austerity, it's hard to "sell" the idea of any big government investment projects because it's easy to counter with emotive responses along the lines of "why are people using foodbanks when there's money to build railway lines".
There's also an anti-intellectual approach in much of UK life nowadays, the way that people sneer at "experts", the way that people prefer "simple common sense" to anything convoluted or "clever". Some might feel that it's much easier to say "why can't they have smarter timetables" than to listen to experts in the industry who will try to explain complications.
But most people aren't against HS2 because of unanswered questions about the number of services stopping at Oxenholme in the 2030s, they are generally against it because of gut feel, because most reactions nowadays are gut based rather than on factual grounds.
Put it another way, the railway would be in a much better position today if we'd delivered all of those projects/ suggestions planned in the early years of the millennium (e.g. the Virgin plan for an ECML-bypass from London to Doncaster) but we didn't do them (partly because we didn't realise how much passenger numbers would rise between then and 2019). If we had done them, it might have taken fifteen years to deliver them, because that's how long some projects take. With 20:20 hindsight, should we have got our shovels in the ground back then? Yes. But we didn't. How do we plan now for the 2030s and 2040s?
If we are worried that we've reached peak passenger, we have to stop all rail investment for growth now Better stick with those Pacers after all.
Agreed - some people on here seem to treat HS2 in a bubble and ignore the awkward fact that, if the reasons they give for not building HS2 *do* happen (falling passenger numbers etc) then that scuppers all rail projects.
If passenger numbers have plateaued then the same arguments apply to all the other investment plans (crayon-based and/or real world).
Replacing Pacers isn't investment for growth, it's investment for quality and safety.
But we are replacing thirty metre Pacers (and twenty three metre 153s) with trains that are at least forty metres long - it's not a "like for like" replacement - we are replacing them with trains that are *bigger* as well as *better*.