What do you mean? WhatsApp rolled out E2E encryption between 2014 and 2016.
It’s by far the largest messaging service that is e2e encrypted by default. I think it’s more than fair to call it ahead of the curve for a service of its size.
But, let's go to the start - WhatsApp started in 2011.
Encryption arrived in varying degrees until there was some pressures to change the amount of privacy messages had for advertising purposes.
Lots in the news at the time.
2018 "Another point of disagreement was over WhatsApp’s encryption. In 2016, WhatsApp added end-to-end encryption, a security feature that scrambles people’s messages so that outsiders, including WhatsApp’s owners, can’t read them. Facebook executives wanted to make it easier for businesses to use its tools, and WhatsApp executives believed that doing so would require some weakening of its encryption."
2018 "Acton said he tried to push Facebook towards an alternative, less privacy hostile business model for WhatsApp — suggesting a metered-user model such as by charging a tenth of a penny after a certain large number of free messages were used up." https://techcrunch.com/2018/09/26/whatsapp-founder-brian-act...
It’s by far the largest messaging service that is e2e encrypted by default. I think it’s more than fair to call it ahead of the curve for a service of its size.
https://www.wired.com/2014/11/whatsapp-encrypted-messaging/ https://blog.whatsapp.com/end-to-end-encryption