How exactly did you put the key into the
authorized_keys file? This answer says the file must use DOS/Windows line endings. I totally do not know if it's true or if it applies to your case; still it is something to try out. Another thing: Linux stores text files as UTF-8 without BOM, every sane Linux tool expects this; I believe Windows 11 likes UTF-16LE, but I don't know what encoding your OpenSSH in Windows expects or supports. I heard OpenSSH-based suite shipped with Windows is somewhat different than pure OpenSSH. What do you use?