I think Sunak is just throwing this election. It's obvious that he goes where the money is. For a short while during COVID 'politics' and the public sector were the safest and most influential place to be in that regard and it looks good on his resume. Now with war in Ukraine and turmoil in China he'd rather not be in charge.
He was clearly selected to "fix" the economy, foreign relations and restore investor trust after Liz Truss tanked it. Labour won't be able to do much unless they can find ways to collect more revenue such as increasing taxes and/or dropping military support for Ukraine. Both either unpopular measures or damaging for foreign relations.
I'm seeing the same thing here with Wilders incoming government.
He can't do any big spending until 2027 or so and even that depends a lot on the state of the global economy and the wars.
So while his plans do paint a better economic picture, they are mostly less than single digit percentages.