>In the UAE, where VoIP is illegal, the government was not able to selectively block voice traffic since it is indistinguishable from text traffic. So they had to ask WhatsApp to block voice functionality whenever a user is in the UAE.
Authorities can selectively block WhatsApp voice calls, it's been done in Oman where I used to live. If I leave Oman and use WhatsApp in an uncensored country, voice calls work just fine.
This is not the case where WhatsApp is registered via a UAE number; the blocks persist no matter where you connect from.
They don't need WhatsApp's help to do it.
WhatsApp voice calls are done over different ports, so only these need to be blocked.
The UAE (and Saudi Arabia) went through the extra step of asking WhatsApp to perform a block server side because of legal regulatory issues. Oman has made no such demand.
My family regularly makes WhatsApp calls to me from Oman; they just have to switch on a VPN to tunnel out of Oman's censorware.
Authorities can selectively block WhatsApp voice calls, it's been done in Oman where I used to live. If I leave Oman and use WhatsApp in an uncensored country, voice calls work just fine.
This is not the case where WhatsApp is registered via a UAE number; the blocks persist no matter where you connect from.