For sure! Thanks for the examples. I didnt know about the country singers.
In practice, intonation in western classical music is actually very fluid. When I played in orchestras, we were always told to play major thirds a little bit sharper, and minor thirds a little bit more flat. It's pretty natural to make leading tones a bit sharper before hitting the tonic.
It's also pretty common for orchestras to tune to concert As that are sharper as they are "brighter". 442hz is pretty common.
Equal temperament is still a relatively new concept. One that was primarily invented for pianos and other keyboard instruments.
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