I don't think this will ever happen. There are just far too many people, with far too many requirements.
For example, I would never use a centralized, proprietary platform for these services. Some folks don't care, but they may want it to work on <insert latest device fad here>. Even if it works on that device, it will likely need to comply with local regulations around the world, each with their own requirements.
If we (humans) can't even get a single, agree on unified service for something 'simple' like web search, what makes you think we'll ever converge on dozens of mediums/services/protocols?
For example, I would never use a centralized, proprietary platform for these services. Some folks don't care, but they may want it to work on <insert latest device fad here>. Even if it works on that device, it will likely need to comply with local regulations around the world, each with their own requirements.
If we (humans) can't even get a single, agree on unified service for something 'simple' like web search, what makes you think we'll ever converge on dozens of mediums/services/protocols?