I don’t know if Google Fonts has changed its policies, but historically it pretty much just hasn’t updated its fonts. Even when repeatedly asked to by the original font’s author. Take as an example Crimson from https://github.com/skosch/Crimson: Google took Crimson Text in 2010 and put it onto Google Fonts, but mangled it in the process, messing up its line-height badly so that the regular and bold weights didn’t match, and that text using the web font would not line up with text using the original font. In 2012, the upstream font made various improvements, and the author attempted upon multiple occasions then and since to get Google Fonts to update the font (or even just to fix the bugs they introduced, for starters!). Others also tried. Well, it’s still broken. In the end a new version of the font (with variable weight) was commissioned in 2018, and Crimson Pro now is. Allegedly the problems in Crimson Text were supposed to be fixed up after Crimson Pro was released: https://github.com/google/fonts/issues/2395#issuecomment-631....

I am aware of them updating fonts that they commissioned. But I know of multiple cases where Google Fonts has been serving versions of fonts that are five or more years out of date, sometimes even broken by Google Fonts. Crimson Text I can kinda understand them not fixing completely, because fixing it would have changed character positioning (thus breaking people’s careful alignment to work around the Google-Fonts-introduced bugs). But there have been other cases where that didn’t apply: metrics were the same, but they just wouldn’t update the font. Might have been PT Serif? Lato? I can’t remember, it’s years since I last cared about Google Fonts.

In short: updating the fonts is not all it’s cracked up to be; Google mostly just doesn’t, and half the time you actually wouldn’t want the font updates anyway—depends on the nature of the update.