Military incidents are very different. While all civilian planes carry transponders that identify them as such [1], military planes usually don't for obvious reasons, so they're much easier to misidentify as hostile.

[1]: https://www.flightradar24.com/

IFF is a transponder system that's significantly more advanced and reliable than civilian aeronautical transponders.

Aren't there systems like this instead? https://en.wikipedia.org/wiki/Identification_friend_or_foe

The US Navy immediately announced what happened. Would you like to take bets on whether Russia fesses up to this one?