I think the OP is stating 2 things, 1 imo true, and 1 false.
Higher ranked players admitted you can be bronze and have an (ok) opinion about the game. And for good reason. There is a saying, those who can't, teach. Sure, maybe your hand to eye coord is not the best, or your muscle memory is not adapting to this particular game, or are not quick enough etc, that doesn't mean you lack knowledge of the game. Same in sports, I'm pretty sure amateur players, retired players, coaches (sometimes ofc ex players), referees, team managers, commentators and sometimes even the public can have an informed opinion, not just the professional players.
As for the 2nd part.
Luck can only get you so far. I rarely read about reaching gold from bronze, but plat from bronze is common. In my bronze opinion there is an elo hell because we are put to the same standards as everyone else, aka silver 5 can supposedly carry bronze 1, gold 5 can carry silver 1, plat 5 can carry gold 1 etc. And that's just a wrong assumption from riot. If skill grows, so does the skill of carrying lower team mates. If you're actually silver up to low gold and are stuck somewhere lower, that's where the luck comes in, because it is harder for you to carry your lower ranked team, than it is for a (high gold,) plat or diamond player. They didn't need luck to get where they are right now.
Plus the trolls and afks, I bet plats learned how to carry despite that, while we didn't.