I'm curious, are these "Chess loremasters" some actual content creators somewhere, or are you just metaphorically talking about some random guys on the forums here?
Is the Sicilian Defense the most dynamic opening for black?

Sicilian is the most dynamic opening indeed, but you need to choose a variation to play. I suggest if you want to play most dynamically possible choose Sveshnikov Sicilian but you won't get your Sveshnikov and the theory you studied especially in online games, people are going to deviate fairly quickly, that's a good news it means that they are not playing in the best way. You'll get advantage in every single game you play out of the opening. That's a big win.
The way to study opening is to play a game, and go through the opening database to see how to play the variation and try to understand the logic behind the moves, that is actually very difficult without a Coach or a book.
Studying directly the Sveshnikov is useless, you can have a general idea on how is it then jump directly and play games, and actually study the moves your opponents tends to play and find a way in the analysis to punish that move. It is very tough but it's the only way to study opening at this level.
The point is that since there is no opening which is blunder-proof, your "success" as Black with the Sicilian is more or less an illusion. When playing against a beginner, you can well win comfortably even with something like 1.e4 a5, or 1.e4 h5.
i never say that i was success as black with Sicilian.
what i said is i dont know if Sicilian should be avoided by beginners, i play 1.e4 c5 as black from 900 to my current rating,
i play Sicilian because i bored with 1.e4 e5, and i wanna try new exp.
as beginner that play some Sicilian games i feel obligated to answer original post question about "heard from loremaster that except accelerated dragon var,the other Sicilian var should be avoided by beginners".
that's all
what i dont understand is, instead answering original post question why you targeting me?
suddenly reviewing my game that i never ask for
and right now you suggest me some opening. did i ever ask opening suggestion to you bro