Decaying through Tiers/not getting rewards

Last year I found out the hard way to you could decay through tiers even though you can't drop through them by playing bad .

I stopped playing for last 2 month because I was on a trip and went from Diamond 3 to Platinum 3 few weeks before season ended .

Just because I had no access to play 1 GAME. Is this to prevent players who forgot how to play the game from playing ranked?

It really makes zero sense and I hope you come to your senses . I have to work toward the end of this year and I hope this **** doesn't happen again .