I m unable to comment on the google fonts, as I have never downloaded fonts from google, but then I didn’t know that they had free fonts. I’m sure Bitdefender would have detected something amiss, and taken the appropriate action.
I don’t know anything about creating fonts, and what determines each font’s file size. Possibly the complexity of the font, I really don’t know. The New Pose font is 702KB, I checked it’s properties. I have many monogram fonts which are in excess of 2MB. Yet they are not overly complex in design. After checking several fonts at random, their file sizes ranged from 25KB to 3.2 MB. So, in my opinion, the file of the compressed font folder, or the actual font file size, doesn’t mean that the larger sizes may contain viruses, or anything else other than the actual font. Possibly unknown to the creator, he/she used a file which isn’t compatible will all operating systems. For example, you can’t use SVG files in PSP. Again I don’t know anything about creating fonts, but what I will say is, if Creative Fabrica assured me that a folder doesn’t contain anything harmful to my operating system, and it is completely safe to use. I would believe them.