Dear Gaben, I would like to talk about MMR boosters and smurfs in DotA 2 ranked in this e-mail.

Firstly, I got my DotA 2 beta key in 2012. I didn't play too much though, but after watching The International 2015, I was amazed how fun was the game.
Hence, DotA 2 is my most played game since then. I'm not the silver spoon, I flamed and got muted, fed and placed in low priority, then one day I looked at my behavior score and saw that it was F. That day I decided to not act toxic because the behavior score system was working well. It showed me how bad a person I was by matching me with people like me, it showed a mirror to me. Now I'm at around 9.500 behavior score.

Now the main topic of this e-mail and the problem is making a lot of people frustrated. The MMR boosters. I think that they do ruin the fun in ranked matchmaking. Since last year the frequency of MMR boosters in ranked matches increased vastly. The mobile number protection system doesn't seem to work. One of the problems with boosters is that you cannot report them, boosting is not allowed. But in the report section, there are only 3 options without including booster and smurf option. In addition, you can only submit 3 reports per week. Whenever I report intentionally ruiners and flamers I get feedback which is pretty nice! It shows me that you took an action against that player which shows that you care. Sadly, I have been reporting mmr boosters and smurfs for a long time but I haven't received single feedback about those reports.

I was going to wait until I collected enough data on MMR boosters to send in this e-mail. I created a text file in 04.22.2019 and saved profiles of these suspicious MMR boosters.
In 4 days, I found out 6 allegedly MMR boosters in my games.

https://steamcommunity.com/profiles/76561198950908504/
https://steamcommunity.com/profiles/76561198923127400/
https://steamcommunity.com/profiles/76561198834797053/
https://steamcommunity.com/profiles/76561198944694420/
https://steamcommunity.com/profiles/76561198019284638/
proof of 76561198019284638: https://imgur.com/a/mWFmyNe
https://steamcommunity.com/profiles/76561198082878032/

As you can see, there is a proof, only one player said openly with no fear of getting banned ( There was quite a few of them since the last year ) that he is mmr booster.
Even though they are in my team or enemy team, I keep reporting them but I'm not receiving any feedback and my right to submit a report stays at 0.

How do I determine the boosters?

First of all, I look at their profile to check on their total matches played. Most of the mmr boosters I have encountered have maximum of 200 total matches played.
Then thanks to the activity feed you have added, I see that the suspicious profile climbed through ranked medals quickly in one week or two.
Example of climbing fastly: https://imgur.com/a/mQGvRk2
The mmr boosters love to play heroes such as broodmother, lycan, meepo, morphling. It's a helping factor to determine the MMR boosting.

My proposal

Now, you can only report 3 times a week unless you receive feedback for the submission of a report. In addition you can only report the enemy team members for communication abuse. If there is a booster that you are suspicious of on enemy team, you cannot report that player. I think that you should add an option to the report section for mmr boosters and those reports shouldn't affect the behavior score. And reported accounts should be flagged for an inspection.

Dear gaben, I know that you are not the one who is responsible for this, but even if I posted this on reddit, dev.dota2 no one would ever look at this.

I hope this reaches out to you, sorry for such long e-mail, I love this game and I'm really upset to see boosters are ruining this.

Best Regards, Berkay.