there just seems to be a greater demand for the blues over the other cherry switches.
Availability :- Blacks > Browns > Blues > Reds (omitted Whites).
Cost :- Reds > Blues > Browns > Blacks.
Generally, human nature steers towards the most exclusive.
After trying MX Blues, I found the Click to be a little annoying and just cannot seem to adjust to the noise. I am using a Monterey switch keyboard which also have click switches, but these are far less noisy, more refined/demure. With all my Cherry keyboards, I use MX Browns even if I have to replace all the switches (due to format preferences), but the Arrow Keys, I always use MX Blacks stems with MX Brown springs. Each to their own preferences, so what's suitable may not apply to others.