Yet, despite what he claims generally (counterpoints, exceptions, unknowns, guess work, don't know how much has survived) in his content, 5 TOP Reasons BROADSWORDS DOMINATED Rapiers in WAR is the title. >.<
Naturally, the talk has revolved mainly around broadsword v. X, what kinds of weapons would be good for dungeon crawling, is the damage assigned to each weapon fair, representative and so on.
I'm not critical of OP, rapier is one of those funny relics for D&D along with a few others kinds of melee weapons; the topic is great and relates to how those weapons are represented in RPG's!
I only urge caution with claims people make on youtube, when well-known historians in their area of specialty have great difficulty reconstructing something, even when they have more first hand sources (e.g. in the case of a battle, having the actual handwritten orders from generals on hand to read) comparatively.