Words mean different things to different people. Personally I have never heard "backyard" as in "in my backyard" used that way. A slang dictionary yields this:

Words mean different things to different people. Personally I have never heard "backyard" as in "in my backyard" used that way. A slang dictionary yields this: >An area nearby to a country or other jurisidiction's legal boundaries, particularly an area in which the country feels it has an interest. https://www.yourdictionary.com/backyard https://www.yourdictionary.com/backyard Which seems spot on, I swear I didn't just write that myself. The WSJ even went so far as to call Equatorial Guinea (in West Africa) part of America's backyard: https://archive.fo/8UjYC https://archive.fo/8UjYC "In my own backyard" would connote what you are saying, but there's an extra word "own" there.