Better speakers/camera/screen/brighter screen on M2
M1 outperformed M2 on read/write
M2 outperformed M1 on content creation testing
Both great machines - not really a need to upgrade from M1 to an M2 unless you want to due to slight performance gains, and if you’re not upgrading and buying your first MBA you can buy either Air and be happy as they’re both great performers
The M1 was 2x faster than the M2 on SSD speeds (real world usage, not just benchmarks). That's crazy! The M2 was pretty much better in ever other test though (as expected), and far more efficient, but did throttle a lot.
No-one should be upgrading M1 to M2 because they need better performance. The change will be barely noticeable. A few seconds here and there on selected tasks is unlikely to make a difference to your life.