New MMR System Does Not Work At All

I am a former 5k (Ancient 5 – Div 1) player, I had not been playing Dota for like 5 years and decided to come back. I played a couple of turbo games and with the big update, I decided to play classic ranks. I was placed in 1.5k MMR bracket. Thought it was reasonable since I had not had any ranks for a while so I started playing, won like 15 games and lost a couple (I still try to get used to the games and when the enemy has too much lockdown and I am killed, my team can't seem to do shit). So after all that, when my MMR confidence level reached 30%, I was given my medal which was Crusader 2 (1.7k). The thing is, I dont want to be have to get a 100 winning streak just to get back to at least 3k. This placement system was supposed to help with the older players coming back but I cant seem to understand how that works at all. I've deleted the game since I did not want to spend anymore time at that skill level and thinking of retiring for good.