One thing worth mentioning as a possibly-contributing factor was that in the very early 90s a lot of the installed base of high-res (eg non-interlaced) color mo

One thing worth mentioning as a possibly-contributing factor was that in the very early 90s a lot of the installed base of high-res (eg non-interlaced) color monitors where still digital RGB (RGBI) which were limited to 16 colors (and often just 8 colors in two intensities each). In many palettes the 8 base colors were black, white, red, green, blue, cyan, magenta and yellow. So, there weren't a lot of colors to choose from. CRTs had RGB primaries so cyan, magenta and yellow weren't generally as legible for single pixel width lines (ie text). I also always assumed part of the choice of blue was that in many locales red, yellow and green have connotations of stop/alert, warning and go/okay (respectively) - whereas blue was relatively more agnostic. So... if you're targeting the widest installed base of displays, out of the lowest common denominator choices available blue was pretty much the obvious remaining choice.