Well it could be simple to you but different states have different numbers for their emergency personnel. Heck even counties and cities within those states have different numbers. Maybe Apple removed it to improve on how you would invoke SOS. 10 clicks well that could be a lot for a real emergency and confusing too
Your guess is as good as mine, but it’s part of the full list of changes that can be found in iOS 10.2 beta 3, per MacRumors.
"SOS - The SOS functionality that allowed users to call emergency services by pressing the power button multiple times on the iPhone has been removed in this beta. According to Apple's release notes, SOS is currently only available in India, perhaps for testing purposes before a wider rollout."