I live in France, and I was born in the early 80s and I can tell you that a lot has been done during my lifetime regarding infrastructure : high speed train lines, highways, subways, tunnels, bridges, etc... And it didn't stop.
I am not trying to tell that France does better than other countries, I think it's not even close. It is just that I know it best.
I think we tend to take everything that works for granted and forget about the difficulties in the past, only talking about present issues. Maybe the convenient road you are using every day didn't exist 20 years ago, maybe it was delayed several years and went way overbudget, but now, you feel like it has always been here, only paying attention when there is a problem.
Which bring up the subject of visible versus (mostly) invisible infrastructure. Large new hydroelectric projects are now rare but compare communications infrastructure of now to that of even the turn of the century and one can see a huge amount of spending and capacity taking place constantly. But buried fiber isn't seen, it's pretty much magic to most people. Cell and microwave towers only get noticed when they're an eyesore but otherwise go unnoticed. It's this invisible infrastructure where much of our investment now goes.
This nails it. Most first world countries managed to build most of their concrete infrastructure in the 60s and 70s. Unfortunately, little since then and maintainance isn't so easy.
It's impressive what China builds - they were decades behind but times changed. A huge parts of Shanghai city were rice field until 1990. Most skyscrappers were build since 2005. And now Shanghai has probably more skyscrappers than any other city in the world. Impressive also the amount of 2 or 3 story highways and the high speed trains.
Now if you look at large infrastructure projects, they are much more expensive, and proceed at a glacial pace.
Except in China, of course.