GDP is a ‘flow’, total value of final goods and services measured over a year. so if a country has a bridge worth $100b, that won’t be included in GDP since it already exists, it won’t be shown when its destroyed/depreciates either. it is only measured for the year its built, no other year.

Yeah, I don't know why I said that the destruction of the bridge would be counted. For GDP metrics, the product/service is assumed to have been consumed entirely in the year it was sold.