It is a constant frustration for a tourist to see a landmark they have traveled far to see covered in scaffolding. This is a photograph of the Spanish Steps in Rome in May 2004:
And this was the same scene a decade later, in October 2014.
A short distance away is the iconic Trevi Fountain. It's more eternal scaffolding than eternal city.
It was the same situation in Venice with the Bridge of Sighs between 2009 and 2011 (though restoration was complete when I visited in 2013).
The problem is certainly not confined to Italy. This is the Padrão dos Descobrimentos (Monument of the Discoveries) in Lisbon, a modernist tribute to Prince Henry the Navigator: