This release, with a stunning new site by the way, is massive. There are 41 OpenType features. Forty one. That might be borderline too many, but not a single one feels half-baked. My favorites are the new compact f and t, simplified u, and basically all of the alternative digits. (I’m a sucker for a flat topped 3.)
There is little you can compare the Inter project to. What started as Andersson’s personal project is now the de facto UI typeface for the web and one of the most popular typefaces in the world. (Likely helped by the fact Inter is free and open source.) Comparing Inter’s influence to Helvetica’s isn’t fair because, well, Helvetica, but it’s also not not fair.
(Pro tip: If you use Slack, you can use this pseudo CSS declaration to set Inter—or anything—as the UI font: /slackfont "inter variable". If you want to reset it back to Slack’s version of Lato, just refresh the app.)