I still see it being useful. A heavy aerial bleed can cause a bleed-out death within about 3 minutes, so timing is important even if ambulances are nearby.

A purpose built tourniquet can stop blood flow when placed correctly on the limbs, and packing gauze, emergency field dressings, and pressure on the torso can limit this loss until help can arrive.

Granted, both will hurt like a mofo, but you’ll be saving their life.

You can get trainer tourniquets to practice with (good if every member of the household is familiar with their use).

I plan on getting a kit prepared and storing it behind a headrest in my car (there are MOLLE style headrest mounts commercially available), as that’s probably the most likely place I’d need to have it for trauma injuries.