Space bar

The spacebar still activates the hand tool, nothing has changed.

If the shortcut is completely gone, it has to be corrupt preferences. Before resetting, make sure your custom actions and brushes are saved out. If that’s not it, maybe a system shortcut or other application has taken over this shortcut. Reboot and launch Photoshop only to check that.

Meaning, you’ve installed the latest Ps version (27.5.0) and the tool changed?

Edit>Keyboard Shortcuts, shortcuts for tools: shortcut is H.

“Help: Select the Hand tool (H) from the toolbar or press and hold the spacebar key to temporarily switch to the Hand tool.”

I didn’t find an setting to change the spacebar.