No thats totally wrong - In Plat the real toxic Players and Ragequitters are coming ... because they think they are Pro and will Flame you for every little mistake you do... So dont expect to get out of silver or gold will improve their behavior. The only thing you can do is report them.
Im not Diamond but Plat 3 and have a Plat 5 acc in Eune but before you think you can reach Plat 5 you have to know that now youre - lets say in 50% of all rankings youre an average Player - to get to Plat 5 you have to become one of the 10% best Players of Eune - and seriously when you cant carry Silver then you dont deserve Gold or higher because it will get much much harder ....
I can give you some tipps and tricks add me skype: pluss777