Oh nice, I like where this is going.
It's definitely true that firearms and modernisation into professional soldiery remove the need for a warrior class. The Satsuma rebellion in Japan (ex. Tom Cruise in the Last Samurai) were samurai more or less fighting against their obsolescence.
Like crazy gun nuts often like to quote, "God created men, Colt made them equal."
I love martial arts but honestly speaking even three idiots with guns will beat a grandmaster in most situations. Infamously, the boxers of the Boxer Rebellion in China believed the age old trope that a kung fu master is impervious to weapons - including the firearms of foreign armies.
But this is a fantasy story with heroes and wizards, so I'm interested in how differently things will go down.