The Culture: This Oldfag Is Lying To Your Face

This is a flat-out lie.

Tenkar is lying to you.

You CAN run B/X (despite being inferior to AD&D) with wars front and center. It's not that hard; Bros, using AD&D, do this on a regular basis--I did this twice in as many months, and I expect more before the year is out, and that's just my campaign; UMBROS, etc. have battles and wage wars just as often or moreso--and you can have your standard adventuring stuff take place interlaced with the batles, logistics, and diplomacy. The warfare gives context to the adventuring, which in turn gives meaning to the warfare.

Tenkar is an Oldfag who is so deep into Sunk Cost Fallacies that he wouldn't know what not-drowning in them is to save his life. Such is the life of an Oldfag Cargo Cultist.

You can see the lack of skill at reading comprehension, his inability to draw inferences, to know how Order of Operations in use of material works (TLDR: if the rules don't say otherwise, it works as it does in reality so consult real world sources) as he drones on.

Don't believe the lies. Wage your wars. You don't need to invent new rules or use external addons; the trick is scaling.