The biggest Catholics's mistake of the 21th century?

Churches without colours.

Mosques are amazing places. 
Synagogues too. 
Buddhist temples too.
Shinto temples too. 
Orthodox temples too.
Consumption temples too.
Etc.

Before churches were colourful, full of joy. They were forums, open places where everything happened.
And now? Very sad white spaces. No decoration. No color. Is it attractive? welcoming?
No.

Why not painting churches like it was the case during Middle-Age. It seemed to work. Church  was very influential at this time.