Ok. Lets refute one statement that makes the rest of it basically null.
You say these are facts. And have nothing to support them. I think you may be confusing facts with opinion.
Now we both agree 1500, should be the turning point. But i cant see any sort of shift in martial arts in that time period.
I also dont see any evidence of society following the martial arts of its guardians.
Now as weapons changed. Then i can see a possibility that historical weapons go out of favor but i am not sure how that applies to the topic of unarmed martial arts.
And boxing has existed as long as martial arts has existed. It is the best indicator of changes to martial arts culture. Rather than bartitsu that had a very short life span.
Fencing. No idea how long thats been going.
First you are completely missing the OPs question. They aren't asking "why did Western Martial arts die" they are asking why these arts have no where near the following, in the West, of Asian Martial arts.
That is in part because, outside of sport, Western Martial Arts were either lost (and rediscovered, case in point HEMA), were culturally isolated (Pankration), were priced out of the market (fencing) or for whatever reason remained niche (Savate, Bartitsu etc).
Why did this happen, look at the difference between the evolution of warfare. You may disagree but your average person on earth defends themselves the way their defenders do. In the West it was the sword, the gun. In the East it was the sword (spear whatever) and the body. So one side becomes a gun culture the other a Martial Arts culture. For gosh sakes the Irish had a martial art that was a form of stock fighting, it died out though because stick does not beat gun.
This isn't my idea btw. It comes down to the simple fact that until that last half of the 20th century firearm ownership was common through out all of the Western world. It wasn't until the post WWII period that Nations, besides the US started clamping down on private firearm ownership. In that kinda of environment people will naturally chose guns over Martial Arts.
Regardless here is how debate works. I laid out a time line starting in 1500 in the West I drew parallels between the increasing use of guns there and how, if you bother to look, study of martial arts fades in the West. I also have said, and please feel free to Google to confirm, how Firearms were not ubiquitous in Far East warfare until the late 1800''s early 1900's to explain why Martial Arts remained culturally relevant there.
You will also note in a prior post I stated that in the 20th Century we now have popular culture being a driving force behind the "defenders". It has some impact in the 19th Century (I specifically named Dumas) but it wasn't until our era that "Pop Culture" could move society so quickly. And look since Pop Culture in Martial Arts took off because of Asian Martial Arts what are most US and European kids learning? Asian Martial Arts, because Asia kept their arts alive and vibrant because they HAD to because when 600,000 Americans died under gunpowder during the Civil War Asians were still, for the majority fighting with Martial Arts.
Now the way debate works is that you don't say "I don't buy it" you actually state fac ts that prove my facts wrong or inaccurate.
So far I have essentially seen "I don't by it." That is not how debate works. If you want to debate please respond with some fact regarding society's practice as a whole as I have. If you just want to do what you have done elsewhere, namely say "I just don't agree with no facts to support my argument, it's just because I don't agree" please save us both the time because otherwise I will simply cut and paste this paragraph.