On the train, on my phone, so not going to go into too much detail but...
The majority of new wind energy is basically fixed price, either via a "strike price" via the contracts for difference mechanism, or via a corporate power purchase agreement.
So, while the spot price of the electricity is somewhat variable, the actual rate paid to the producer isn't. Most of the variability comes from balancing costs (ramping up and down gas powered stations, interconnectors, pumped hydro, battery etc.) or paying constraint payments when the wind power can't be used.
When these projects are consented, there are some fixed costs and some variable. The developer has to commit to this fixed prices while some of these costs can go up and down (hint, they don't come down that much). Thst said, the CfD mechanism has brought simply huge reductions in the last 20 years, from over £150/mwh to as low as £37/mhw iirc. However, it's now widely agreed that because of higher cost of capital, steel costs, inflation etc. These low prices are not achievable, and that the projects aren't viable. (hence why no bids last year in AR5 and an increase in the target strike prices for AR6)
Now. Labour. Great British Power. Not sure what their exact plan is, the details haven't been spelled out yet. My thoughts will be lower cost capital, and maybe some level government backed insurance. Both of those are quite significant line items in the overall cost build up of these major offshore wind projects, and the only aspects I can see where a dent could be made. Basically, instead of pension funds and other major private investors making their returns on investment, it'll be you and me via gov issued money. The insurance is a guess.
The challange for the gov will be the same as for everyone else - the "experienced" development teams are already stretched, with anyone showing a hint of past experience and nouse in very high demand. So they're at a disadvantage, meaning there's always the chance of poor investment choices.
The devil will, as always, be in the detail.
So far they're making some good, high profile hires so it's a promising start. I'd say, watch this space.