Agree with you sadly. The reasons it will not happen are many. The main hurdle is the massive, long term, funding this will require. The levels needed will be too big to sustain.
I was involved in Rosebank project (Chevron Aberdeen) before it was shelved. Whilst not on this scale the subsidies being offered to buy the line pipe from Tata Teesside, and use coaters near Edinburgh, were huge. Ultimately didn't happen. The numbers are simply too big with so little chance of a long term return.
In my current role I am dealing with fabricators in China (not shipbuilding, but large scale spool manufacture) and in my previous was involved in massive module packages built in Korea. What I can say with 100% certainty is this country will never be able to compete commercially with either. Add in Japan to the mix. MHI are subsidies to incredible levels by the Japanese Govt. They still struggle to compete.
I can only mirror your comments and experience unfortunately. The cost to reintroduce large scale heavy industry and s too prohibitive. Companies like BAE exist only because of significant government funding. They are almost nationalised companies as they wouldn’t exist on their own merits (certainly for government funded projects anyway).
Korea isn’t just ahead of us, they’re light years ahead based on advances in technology, basic infrastructure and as similar as working practices.
We can’t compete even in established yards, let alone one with no workforce, no river and no contracts.