Not on a button, it should not.
it's a simple click, it should not activate the panning but just click.

Sorry, but for me, it's a bug!

It breaks the system of modifier keys.

Emulate 3 Button Mouse has nothing specifically to do with panning. It is a feature meant for input devices without MMB. It maps Alt-LMB to be interpreted as MMB. That's the point of the feature, and that's how it works. So it's not a bug.

that's not right. When you open a pie menu the emulate does not have to work because it is in another context. however, you cannot use the alt option button to do a different action in the pie menu. For me we should be able to do it. It doesn't interfere with the functionality of the emulate.

+1 with jemian, ALT is a modifier key, Emulate 3 Buttons breaks modifiers keys system when it could work correctly.
I don't know if you know it or use it, it's really powerful and helps to keep clean UI.
It's not for the beginners for sure but, we need to keep it and improve it, make it work will all keymaps.

You can still keep the panning when pressing outside a button, I don't see the issue there.
Juste disables Emulate 3 Buttons when the cursor is on a button in the UI or a pie/menu.

Maybe it's not a bug because it doesn't interfere with Blender's functions but it does prevent us from using this option key for the pie menu buttons.The emulate shouldn't be active in this case.

Given that "Emulate 3 button mouse" didn't break Alt+<click> functionality in old Blender versions, it definitely feels like a regression, an oversight, and slightly unfair.

From an accessibility point of view, I can't effectively use newer blenders with a track pad. (Which I also use on the PC).

Would be great if this could be revisited.

Maybe will you add option: changing alt to other key