Except people at one point realized that IE is shit and switched to better alternatives. I don't see this happening with WhatsApp - everyone and their great grandfather uses it and all other messengers are niche occurrences
Reading the links provided would have answered your question.
Provisions for ensuring a higher degree of data portability, interoperability, and access to data for the platform's business and end-users.
There is some discussion on if this means that 3rd party apps can develop for chat platforms, and it seems so at face value. eg, gaim/pidgin or trillian can make a come-back and you can use whatever client you want to access the Whatsapp platform. Nothing would then stop an app from natively integrating whatsapps apis alongside their own.