It is that deep. It’s a global sport that’s accessible to the poorest of countries.
You think pro boxers have hundreds of amateur fights and dozens of pro fights before a title shot unnecessarily? They go through these extensive preparations because they know it’s all necessary to succeed. If you could just walk in against a highly ranked fighter with a limited background, everyone would be doing it.
I don’t care how many knuckleheads Stipe and Ngannou crush in mma, they’re a mismatch for any established/ranked pro.