PSA: This is not Season 5. This is Season 6
If you want a rank in Season 6, then you grind for it in Season 6. Not Season 5. Are you really so lazy and arrogant you think you deserve something this season for last season's performance?
The point of the Ranked system isn't to make you feel good. It's to give a competitive system to test your skill vs others. The seasons reset the ladder because it's a new season with a new ranking
If the ranks weren't difficult to get, they wouldn't mean anything.