I think it is probably currently unaffordable given the financial backdrop and there are more urgent issues needing addressing such as the economy, the cost of living crisis, the state of the NHS etc (for now). That said, I think the effects on Nursing and GP issues should be fully considered and training in these areas be free, or at least better subsidised.
However, it is about the right time to explain what he will do rather than what he wont do and to start focussing on how his plans will be funded. If he ducks and dives on policy and taxation I worry that it will play into the tories narratives and cause potential switchers to wobble and keep Sunak and his mates in power. He needs to start to give clarity to what he will achieve, how it will be paid for and sell why it is good for Britain and its people.