[dragonwriter]

> There is no need to have the public-facing identifier be the unique identifier

Yeah, there is: it's a major UX improvement, because the URLs at issue are entry-point URLs, which need friendly names for the same reason domains for public-facing services (which are key components of entry-point URLs) do.

It's true that in the general case objects don't necessarily need a URL component that matches their friendly name, but this is not the general case.

[alistairSH]

It seems like a major UX improvement, but is somebody looking for Prince Harry's Instagram account going to know http://www.instragram.com/sussexroyal, or are they going to enter the app and search "Prince Harry", click the first link, and then "Favorite" that account for future reference?

I know I personally very rarely type a direct URL. Either it's already bookmarked, or I google it.

[dragonwriter]

> It seems like a major UX improvement, but is somebody looking for Prince Harry's Instagram account going to know http://www.instragram.com/sussexroyal

Instagram accounts (and similar social media IDs) are often communicated in print, and parsing and accurately transcribing things that work like natural language is a lot easier than something like an arbitrary base36-encoded identifier.

They are also sometimes communicated via orally or via radio, where being able to hear and remember is even more affected by the using natural language.