"Non-GAAP" is the new "pro forma".
Remember the exciting dot-com boom days? Everybody was reporting "pro forma" results. Pro forma in the 1990's turned into a euphemism for "We just made this stuff up". But after the dot-com bust and a series of accounting scandals, the phrase pro forma turned into a bad word on Wall Street. People swore off that pro forma nonsense and returned to the good old GAAP numbers.
But we all knew that that wouldn't last for long.
But people aren't being so cheeky as to use the phrase pro forma. No, the magic phrase is now "non-GAAP". Punch that into your favorite search engine and watch all the people reporting earnings that do not conform to generally accepted accounting practices.
Let's see how long before this ruse finally collapses. And how much money people lose as a result.