Just a few days ago I asked if Centurion lounges have gotten so crowded no one goes there anymore. The lounges are nice, an improvement on their US airline lounge alternatives. They’re stylish spaces with decent food and beverage programs.
Ultimately there are too many people who have been eligible to use the lounges, who have wanted to use the lounges, relative to the size of the lounges. There’s only so much they can do to expand capacity in the airports they work in (and larger lounges are going to attract more people who still stay longer, since currently some people – like me – often stay away precisely due to the crowding).