Looking at your stats, it seems you have decent winrate with certain champions. Maybe you're more comfortable playing them and you don't realize it yourself.
Lucian has 22games but 27% win rate. I would suggest to not play him in ranked until you learn to utilize his kit better. If anything, this champion is dragging you down or your decision making doesn't work with said champion. You also have a good amount of other champions in sub 33% win rate, like, a good amount of your games with less than 33% win rate with these champions might be a good reason of why you're in the rank you are now. There are plenty of players who can hit Master tier being a one trick pony. I am not suggest you to be a one trick pony but I just don't recommend any player to play such a big list of champions across so many roles. It's just not proficient or efficient if 'winning' is your priority.
So far, I counted 118 games from you with less than 33% win rate. A lot of these are actually in the 20-27% win rate range, and there are a handful of 0% win rate. Imagine what rank you will be if you didn't have to lose at least 2/3 of these games? I am sure you can do the math yourself on winrate > LP gain > rank. Practice on basics, improve yourself, try to play what you are comfy with and watch streams/read guides to help yourself improve. So you know, silver and gold have trolls and afks as well. Maybe at a lower rate (which we might never know) but it exist.
Another thing I would like to mention is that you cs count per game on top/mid/adc are way too low. Looking at Fizz and Lux, you acquired over 100 games with these 2 champions you play the most, and the avg cs is around 110 or less per game. A game can't be surrendered till 20min, most games takes more than 20min to win. So your cs count is less than 5/min which is not optimal. There are a couple of Bronze 1-2 players I know who can get 7-8cs/min on average. Until you at least solve this problem, I can see why you stress AFK so much when you play so much Fizz. Fizz can 1v9 if ahead. CS = gold, gold = item, item = ability to 1-2shot any carries you see as Fizz. If Lux is ahead, lands a binding (I assume most Bronze players are too stingy to buy MR by mid game due to bad farming ability), can delete people from the game in 1combo. With a low CD ult, she can do this repeatedly and secure more objectives for team.
Take my opinions with a grain of salt. But I would recommend you to not type to anyone in the game for 5-10games in a row. You can ping, but don't type no matter how frustrated you get. If people are feeding, just ignore them, and play. If you can do this, it's the first step of 'you', 'yourself', are trying to improve. Don't worry about others, let them worry about themselves. Good luck with your climb. Hope my opinions help.