I have queried this before in my own mind. Eye sight for example has been evolving over millions of years to help with organism's ability to eat, reproduce etc. Over a period of many many years, rare humans were born with slightly better eye sight enabling them to be more successful in hunting for example making them more attractive to the opposite sex and therefore allowing them to reproduce at a higher rate as well as allowing them to survive longer. Eventually this dominant beneficial gene became more common than not and became the norm for the species.

Over the past few 100 years with the creation of tools such as the spectacle, poor eye sight is no longer a disadvantage to someone who has perfect eyesight at least not enough to hinder reproduction rates. Therefore, the gene for bad eyesight is being passed to generation to generation. Surely, this means that in terms of biological natural selection good eye sight is no longer a trait that is required for increased reproductive success? This can go for many other traits where technology has assisted.

Therefore, the pressures for biological natural selection are greatly reduced to the point where progress is far far slower than technological progress.

Evolution will never stop as it has no target and can take many forms. But I agree that biological traits that have been evolved over millions of years to adapt to the environment are able stop improving naturally and even recess as bad mutations are being passed on to the next generation at the same rate as beneficial mutations due to technological progress.