That's strange. I'm on iOS 17 on my iPhone 11 Pro and it's just fine. Maybe the battery issues mentioned are due to normal degradation?

I don’t feel like my iPhone 12 mini is slow with 17.4? I guess it doesn’t make sense t argue about subjective experiences but I just wanted add a some anecdata.

Battery feels just fine (over a day, that is with Tailscale turned off [did get better some updates ago.])

Do older versions of iOS still receive security patches?