The pricing structure will change.
Reform have started the ball rolling, even if they call the auction system a subsidy (factually wrong), it does open up the topic for debate in parliament.
Trump did a similar thing in the USA during his first term as president. What happened was that Texas, the oil trading capital of the world, invested heavily in wind and solar.
The bottom line is that wind and solar are the cheapest forms of generation, so investment will head there because the returns are better.
Why would they invest in new generation, even if it is replacement generation, when the cost is double for the same wholesale price.
What I think is the problem is the general perception about power generation, these are long-term projects with even longer term paybacks, but still profitable (unless you are French).
Too higher priority is currently being put on 'intermittency', all generation is intermittent, gas especially. The gas supply has to be managed, it is not as if the bulk natural gas supply is infinite. We don't notice this as consumers, but the large generation companies have to carefully manage and arrange for future deliveries, which is why the price of natural gas is volatile.
If we relied on coal fired generation, even assuming we had 60 GW of capacity available, how much do you think a tonne of coal would cost, more than the current price of about £100/tonne, before processing.