Anderson Silva is the "GOAT" because..
He is a disciplined fighter who can think deeply both in and outside of the ring. Most of these UFC fighters I see are the "badass mofos" that look to **** **** up.
Silva probably has the record for most slipped punches and counters even if you combined 5 fighters together. Rarely swings wild as well, shows good composure under pressure.
Don't knock me for this assumption, I don't watch UFC besides the ones my buddies are willing to pay for at their house. Although I have seen a lot of Silvas fights.
He shows the art form of MMA, not roughhouse tactics. Sure roughhousing works, but I watch boxing for it's sweet science and it looks to me like Silva knows his chemicals.