They had tons of handy features in Google Maps before it was redesigned using Material Design. We used the route elevation data often to plan hiking trips with our parents to determine if they would be able to make a trek. The map scale was absent from the first couple releases and when they reintroduced it, it would only appear on zoom and then vanish. It took 3 or 4 more releases for them to finally add an option buried in the settings to make it always on.

I'd like to say they did this to present a clean minimalist app but the recent incarnations of it are more cluttered than the pre Material Design version. Sure you can tap on the map to minimize the clutter and then tap again to make it go away completely but tapping also drops a pin if you hold it for a sixteenth of a second longer. And I hope your touchscreen isn't super sensitive because it'll detect that flutter as a double tap and then you're just zooming.

It was part of Google+ until very recently. So my guess is, that they just moved it.