I was pondering this some and it dawned on me that the issue may actually be related to the style of tongue in the various lace up boot offerings. I've been wearing the same brand and style for so long that it didn't immediately occur to me that other boots may not have a fully attached tongue like mine do.
Even if I wore mine without the laces, no slag would get to my foot due to the tongues being the style that is sewn onto both sides of the upper almost all the way to the top. You have to fold both of the sides in around your ankle as you lace them up. Boots without that type will be more prone to burnt feet. My apologies for not catching that sooner.
Mine are like this, if you find some that you are considering, make sure they are similar.
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