Juniper link-protection feature

I was reading about this feature and I'm wondering if someone can educate me on why you'd use this:

https://www.juniper.net/documentation/en_US/junos/topics/topic-map/link-protection-aggregated-ethernet-interfaces.html#id-example-configuring-aggregated-ethernet-link-protection

If you had 2 physical interfaces in an ae interface, why would you consider using this feature? If I am reading right, does this then make it active/passive interfaces vs active/active? Trying to study and learn as many knobs as possible here in JunOS.

I suppose I could see this feature making sense if you were say, hooking up active/passive HA firewalls downstream, but wondering other uses for it?

TIA