The idea that Starmer could go into the next election promising to join the CM, or have a referendum on rejoining the EU, and not destroy his chances of being elected is fantasy. The sort of fantasy politics that lost Labour the election the last time round. Voters, rightly or wrongly are scared of voting for Labour, due in part to having the media and the powerful briefing against them, but also due to lost credibility of their last manifesto that promised all and sundry, It's actually miraculous that they are in with a shout given the size of the defeat the last time around. If they do a good job, and they build trust with the electorate and EU partners, it just might be possible if the demand was, and the conditions were right to lead on that when asking for another term.Starmer has made core policy choices 18 months out then. He's has ruled out the SM/CU. -4% to -5% loss of GDP is at the lower end of estimates for Brexit's damage, some now put it at -6% to -11%. These are not small numbers, and given the nature of the beast it's easier for the damage to increase than the opposite. Starmer thinks people should just accept it, and unlike the Tories he knows all this and understands the damage, but also knows telling the truth will offend people so he doesn't.
I'm weary of a starting point for a political project being this disingenuous, untruthfulness on this subject has already done a lot of damage to the UK. It is a type of moral corruption.
When a polity undergoes the polarisation the UK has, people move away from the centre and towards the extremes each time there's fresh disagreement. Witness the Lib Dems poor polling, when in the past Tory polling being weak and Labour having a leader that isn't threatening to Tory voters guaranteed strong Lib Dem polling. It wouldn't be surprising if the Greens improve their results if Labour disappoint people.
They're telling you what they're going to do, you just don't want to hear it. Blair was just on Peston explaining it all. He wants less tax and less spending (what did Truss want again?), presumably he wants the private sector to do the state's job (what did Truss want again?), which means no new infrastructure and expensive houses. The Tony Blair Institute (known funders include the US state department and the Saudi government) has 100s of employees, they'll be one of the thinktanks competing to write Labour policy and they have far more resources than most. What Blair comes up with is going to be more professional than what Tufton Street could ever dream of, nicer slogans and soundbites and none of the libertarian wild west madness, but it's also going to the same old neoliberal/Thatcherite gruel.
There is a quick way to tax less and spend less. Axe the tax rate to a below 20% flat rate, then kill the NHS and most of the military and anything else until the low taxes cover the spending. Not sure where the growth will come from once the state has removed itself (whilst every other advanced economy has state investment into their economies in various ways, including the US), but "tough choices" and all that. You can best see how ridiculous it is once it's taken to the logical conclusion (Truss's great sin).
I'd rather Starmer didn't fraternise with Blair. However, tax less spend less in itself not a bad outcome if it doesn't harm / disenfranchise section of the populace, particularly the vulnerable. Blair's government targeted unemployment quite successfully, which reduces the burden of tax on an individual level as more pay tax. He also brought in the minimum wage, which may not have been that effective in reducing spending by reducing top up benefits and harms as a result of very low pay, but not a bad idea. The state spends far to much subsidising employers who do not pay a living wage, and who do not pay the costs for the training/education of their employees. You can spend less if you priorities health prevention, sort out the care system, and not rely on agency staff. Even school breakfast clubs can impact spending and tax positively longer term by reducing harms caused by poor nutrition, even if you do have to spend some as investment up front.