There are very few European countries that have decent systems to consistently bring through athletes. The UK, Poland, France, Spain, and maybe Italy. Every other country just waits for occasional exceptional talents to emerge. It's laughable that Germany, a country of more than 80 million people, didn't win a single medal at the last Worlds.
But even the countries with a good system are outsourcing talent development to the NCAA, especially in the sprints and jumps. Most of the UKs best young sprint talent is interesting he NCAA (Anning, Ojora, Zeller). It's a smart move for sprinters as the NCAA has an amazing track record at producing global medallists in this events.