Part of your post confuses me but as for the rank of players you are seeing its simple. You are matched in your game by your MMR, not your rank. You can be Silver 3 and 4 and still get players that are in Bronze on your team.
I am currently in that situation.
3 weeks ago i was Silver 3 about 1 win away from my Silver 2 promos. Then I hit a rough couple of weeks with a mixture of bad games followed by games with trolls, players DC and stuff like that. Next thing i know i feel back to Silver 5.
Now when you reach 0LP it takes a lot of losses for you to demote back to Bronze but your MMR still goes down. So if you are losing more than you are winning, but winning enough to keep from demoting then you will have the MMR of a Bronze 1, 2, or 3 while still in Silver. Also take in the fact that some could be duoing with 1 being Silver and the other low Bronze.
Its rough when you hit long losing streaks no matter if its from trolls, afkers or just games you played badly because you will start to get matched with players who are less skilled with less game knowledge.
Believe me i know, like i said, im going through that now. I mainly support but right now i cant even que up support because im getting matched with people who some are still in their placements and are in their 1st ever ranked games. Their game experience is just too low to try to support. So im just queing top and mid and forcing myself to try to call more shots when i see them just wondering around not knowing what to do.