Two others already responded but I'll echo them. Office space in the city centre of Edinburgh and Glasgow is remarkably cheap and plentiful. Living costs are very low (even in these cities) for what you get compared to the suburbs in the USA. There is some brain drain, but the culture and quality of life is the "pull" that the original article was describing. Most Scots who are brain drained away come back to raise kids or retire.
In Edinburgh especially, there is a lot of empty high-quality office space at the moment. You can negotiate very favourable terms, not limited to long rent-free periods, well spaced breaks in contracts, and more-office-for-no-extra type deals.
> If wages are so cheap, doesn't that usually mean that real talent leaves to find better jobs in the USA or London or similar places?
The cost of living is cheaper and quality of life is usually considered better, so when making personal decisions about where to go it's not just a simple wages comparison.
Wages are cheap because cost of living is low. If someone wants to find "better jobs" somewhere else, they generally have to accept higher cost of living. Those remote jobs where you get San Francisco wages and live in the rural mountains are fewer than is ideal.
Remember that some people dont want to go to London. They want to live in Scotland. (this same argument applies to many places, some London people would hate to move to Scotland, some people from rural England do not want to move from that part of rural England etc.). So there is a pool (of some size) of labour that really wants to stay in the area and is probably willing to earn less rather than move.
Is office space really that cheap in Edinburgh or other large cities?