People are too docile and glued to their phones to actually do anything about Western decline. I mean, just look at birth-rates in Western society. If people can't be bothered to breed, they sure as hell can't be bothered to rise up and throw off the yoke of waton capitalism.
In this case you can also say Japan or China are also on decline, as both have low birth-rates. On the opposite trend, the countries with the highest birth rate are not necessarily the most successful. When the birth-rate was high in Europe, it could only be managed because millions of people emigrated. The demographic pressure would have been too strong otherwise.
As for the West in decline, I think the biggest issue is that inequality of wealth have been increasing again since the late 80s. The wealthiest percentage of the western population didn't see a decline - on the opposite, they have amassed more and more wealth. The middle class and the poorest see their living conditions decreasing and fight among themselves for a part of the cake getting smaller and smaller - hence the decrease of birth-rate.
I don't believe in communist utopia but unchecked capitalism without the notion of common society is a disaster and as long people are exclusively focused on themselves we will see our lives fetting worse while a little percentage of people will benefit from it.