Every flat map projection distorts something, so every projection has to optimize some parameter and trade off other utility. I'm constantly amazed at how hung up people are on apparent size of countries. If size is your thing, use some other projection!
Mercator is and remains popular because it preserves local angles and shapes, which makes it simple use this projection to navigate by rhumb lines (compass headings). Because most maps people are exposed to are designed for navigation, it is the most commonly seen projection. And yes, it distorts size and is largely unusable past about ± 70º latitude. Every map is a compromise.
Mercator is and remains popular because it preserves local angles and shapes, which makes it simple use this projection to navigate by rhumb lines (compass headings). Because most maps people are exposed to are designed for navigation, it is the most commonly seen projection. And yes, it distorts size and is largely unusable past about ± 70º latitude. Every map is a compromise.