There's a baseline gear expectation to play PVP without getting hopelessly statchecked by your opponent. If you don't meet the gear expectation, regardless the player level you will lose due to the stat difference.
It's not hard to get the gear sets needed to play the game semi-competitively, but it's not as though you can just jump into PVP and expect to win without putting in some work to mitigate the resource gap.
There are already systems in place for matchmaking with gaps. If the PVP rating difference is too large, you gain 45 on win and lose 5 on loss. This means you can climb with something as bad as a 10~20% winrate.
If you are struggling in plat, just remember that the people in plat are there for a reason, and once you gear your characters properly and build a functional team on a good week it should be no effort at all to climb.
