Flute notes are too short and slurs don't always help
As discussed here https://musescore.org/en/node/320462, flutes are not holding their sound to its full length.
1. This can sound very off for long notes. The pause should stop being proportional to note length at some point.
2. You can get full-length playback using a slur. But this doesn't work when the slur starts at the last note of a tied group of note. Starting it from the first tied note can work, but is often unnatural notation.