I didn't see mention anywhere of a license. I also don't see anywhere to download this from. Is this release equivalent to saying "here is an OFL metric-compatible Arial," or are they releasing it in the sense of "our products will now look like they use Arial, but aside from that this doesn't concern you."?
This page, which is poorly designed¹ to the point that it supports the idea that this is all an in-joke rather than the work of pros, appears to suggest that this is a purely commercial work: https://abcdinamo.com/licenses
¹ Seen while scanning: (1) Scroll down, then up. Boo. (2) Leading cramped beyond "style preference". (3) Bulleted list badly styled in a way that requires work. (4) No attention paid to tracking where it's needed (e.g. small all-caps type). (5) Some terms (e.g. "First Designer") capitalized inconsistently. (6) '&' used in body copy.