This is such a misuse of the word poor. Have you actually been to a poor country?

The UK is poorer than the US - sure. But it's wealthier than most other countries in the world. Not just in terms of GDP per capita or average household wealth, but also in infrastructure terms - the cumulative effect of being a wealthy industrialised country for so long is a huge amount of infrastructure.

I think it's fair to say that UK wealth growth has slowed at the same time as many other countries have caught up. So the UK is no longer the leader it once was. But that's very different from saying it's a poor country. It's just not.

By your definition 95% of the world population live in 'poor' countries. I guess if that's how you want to use the word that's up to you, but people outside of your bubble will literally not understand what you are saying.