ん～？ まあいいか。
単純に以下の記述で問題なく動作してるけど。
なんか別のキー入力割り込み系アプリ・ドライバがおるんちゃうか？
Win10 Pro 22H2 19045.7417(ESU)、Google IME 3.33.6130.0、AHK v2.0.26

#Requires AutoHotkey v2.0
#Warn ; Enable warnings to assist with detecting common errors.
#SingleInstance force ; Determines whether a script is allowed to run again when it is already running.
#UseHook
SendMode "Input" ; Recommended for new scripts due to its superior speed and reliability.

,::b