very true but the intention of that why is different,
the intention or purpose of a coverage is to know how much of your code is tested and how much is pending, whether it is in isolated or integrated shouldnt matter, isnt it? If i have an application with 5 components and used in 6 places to be tested for integration then when i look for coverage i wonder if a dev would/should think about is the coverage from isolated or integration environment
True these are opinionated topics