OP's views on British companies are questionable.
> Consider: Dyson: From a Wiltshire barn to a global technology powerhouse, now innovating in Singapore and Malaysia.
The founder of Dyson is a Brexit proponent who enjoys outsourcing and playing games with tax havens. I doubt he's doing any "innovating" in those places.
Does OP think CS prodigies are building world changing stuff? 90% of the top 1% are building SaaS. Perhaps the 0.01% get to work on actual foundation model ML research or cutting edge theoretical CS. Everybody else will optimize buttons in CSS to pay their bills. Software just pays more, it isn't an exception to economic forces.
Implementation is what takes that raw R&D and uses it to solve problems real problems, which is where it derives it value. Armies of people slightly modifying slightly different saas is how those foundational ML models end up in the everymans workflow.