The problem is that a player who in previous seasons fucjed up their mmr by losing alot of games, now is forced to have super low lp gains and super high lp losses, i for example gain 8-9 and lose 19-24.
Here is the catch.
When you go in win streaks your mmr raises but in bronze win streaks are hard to achieve as the possibility of getting matched with a bad player or troll is very high. Now assuming you are not the feeder or troll, the odds are 4:1 for the troll to be in your team vrs 5:1 to be in the other team. That means you should have a little over 50% winrate. However the big win streaks are real hard to get since you must be extremely good to counter a potential feeding from you own team.
What i mean by that is that a platinum or diamond player with 8-9 lp gain and 19-24 lp loss would have a chance to make it out of bronze since they are too good for bronze standard, but a silver or gold player would have an extremely almost impossible time making it out of bronze.
Now you will hear alot of smart asses saying that a silver or bronze player with 8-9 lp gain and 19-24 lp loss could make it out of bronze, but that is bogus. They are not taking into account that the odds of the troll- feeder might be in their team, and the odd is like 40% and thus real hard to win 3 games to compensate for one loss ( like i have to do) for example.
I had a nasus in my previous game who didn't know how his q stacks worked, we tried to explain to him but he was so stupid that couldnt get it. He finished the game with the amazing 6 stacks to his q. When people get over 300 usually. That shows the kibd of people you may have in your team in bronze, but there kinds of people have a higher chance to appear in the enemy team.
The thing is you can't have a huge win streak like that. Also you must consider the fact that sometimes you are last pick and thus are forced into a role that you don't like. Even if you are very good in that role, carrying the game might not depend on you, you might be an amazing support but have a stupid adc, or be an amazing adc but your support may be terrible, feeding the enemy adc and diving in for kills. Therefore i think riot's system is flaud since a silver player could not get out of bronze like a diamond player would.