Re: There was almost a standard here
From Wikipedia:
"WinZip, starting with version 12.1, uses the extension .zipx for ZIP files that use compression methods newer than DEFLATE; specifically, methods BZip, LZMA, PPMd, Jpeg and Wavpack. The last 2 are applied to appropriate file types when "Best method" compression is selected.[27][28]". It doesn't explain how clicking on that executed an autoextractor, but maybe I'm overthinking it and people actually did decompress it with a compatible archive program and manually launched the files within. It's a little weird how many people will go to rather extreme lengths to execute code that is so suspicious. Last year, El Reg posted an article describing a partially successful campaign requiring users to download a RAR file and then decrypt it just to open a PDF, which some people in engineering fields actually did.