[transpute]

In some threat models, it's more feasible to protect a portable flash/SSD drive than an entire laptop.

In other threat models, laptops/tablets/phones could be physically secured in a safe, or kept under direct physical supervision.

[sudohackthenews]

Yeah, that’s what I was alluding to. I think the OPs point still holds here- both of those are quite a bit harder than the built in Mac solution