It’s the Swiss German suffix for forming diminutives (as “booklet” is to “book” in English): https://en.wiktionary.org/wiki/-li#Alemannic_German

And that’s because those codecs are developed at Google Zürich. Knusperli, Brotli, Brunsli… those are all pastries (Brot means “bread” in German).

They are developed in switzerland