Sorry I didnt use the exact vernacular. You are acting like TWITCH, a live Video broadcast site is infallible, or that the recordings from twitch are infallible. Furthermore youre not addressing the crux of my point of why they dont take player evidence - be it twitch or a guy with a 1990s camcorder recording his monitor : There is the potential for that information to not be correct or presented in a way that removes context of what actually is happening or being done (cutting the stream early, starting said stream mid action, framing the action in such a fashion you cant see everything going on - none of which requires video editing). This doesnt include self submission videos where the videos arent on or from twitch, or videos that are uploaded to twitch after being edited. They pretty much lump together player submitted information as short hand because in practicality most of it is gonna be junk or biased. Imagine being in the position of having to watch every video or screen grab submission from someone who suspects another player of hacking, then having to do follow ups for each individual case. Its a sisyphean task.
As for shadowing an accused player, how do we know this isnt the case as is? I keep seeing people say "SE has said this" but Im not finding recent examples that outlines the exact duties of what GMs do and dont do (or local teams for that matter). For all we know, GMs could be shadowing accused players via reports and kicking those cases up the totem pole to the STF.
Beyond that, no I dont agree with WoW handles it much better. Ive seen stupid botting shenanigans in WoW first hand that is just as bad as it is here. Is it always that bad? No. Is there room for improvement? Sure. Is it so drastically better than FFXIV? No, not in my opinion. It has been as bad and as good as WoW has had it on average.
Lastly, color me a bit skeptical if I take what you say that only 4 people manage the entirety of policing the player base. Where does this information directly come from and what are the specifics. Just by briefly searching around I only found a small bit of information regarding the STF and their purview - Mainly that they handle botting and third party program issues that can interfere with the game. Based on what I read (reddit posts/articles that are 3-4 years old), they arent reviewing every bot case but are are probably operating off of server data, reports, and algorithms. Furthermore it doesnt say that they alone deal with all of this by themselves with absolutely no outside support from local GMs. If anything, I found posts and reports that suggest the opposite - GMs do handle some of the local issues, at least in so far as hacking and other low level issues that require more involvement. Maybe Im wrong, but I would like to see where this came from. Cause unless you got a recent interview or article that says specifically the STF handle every single issue of botting and hacking and does it all manually and is operated by only 4 people, I am more likely to chalk up this "4 people in japan handle a few million players" as nothing by misinformation or misinterpretation of old reports. That isnt that big a stretch considering how often this player base misconstrues half of what the devs say on a regular basis.