The technology of modern reactors ,like the one in the article, is a greater advancement from early reactors that the 1900th century electric car to a modern one.
The materials, manufacturing techniques, fuels, controls, and components are only achievable due to modern advancements.
The latest reactors will be cheaper, more efficient, and safer. They are a necessary stopgap to overcome the transient nature of renewable energy in the UK and an important piece in ensuring energy availability and detachment from from fossil fuels.
We know historic nuclear is expensive. Cost is the entire point of SMRs. Let’s not use reductionist logic to make a complex problem seem simple. It is complicated and whether SMRs succeed is still to be determined but there is good logic in the aims they have set out and I hope they succeed.
As for renewable, it would be wonderful if we could store energy to overcome the ebs and flows of power they currently produce, but I am not aware of any technology currently allowing this to sufficient costs and practicalities. This is where nuclear may be required
It doesn’t matter if you produce 400% the required energy in a year with renewables if we have to go without even a fraction of the time.