Currently, the highest MMR calibration possible in Dota 2, in a completely fresh account, after the required games to unlock ranked play, is 6k MMR, meaning that the cap of 3.5-4k that has been around for a long time is no longer valid, if you are good enough, as many pros do, you could calibrate your account directly
Is 5k MMR good DOTA?
Theres no denying that 5k is indeed a good MMR and only achievable by the most skilled players in the game, sure, it may not be enough to get even close to the pro level, but it still represents a high level of knowledge and mechanics of the game as a whole.
What is good DOTA MMR?
According to these Valve stats, the average Match Making Rating is 2250. 50% of the DotA 2 population is below that rating, and 50% is above it. While Leaderboard ranking starts around 6000 (top 200 players of each continent), the top 1% begins at 4100.
How is MMR determined in LoL?
The MMR system in LoL will put two teams of equal average elo rating against each other, so for example if team 1 had one gold player, one diamond player, and three platinum players, the other team would have 5 platinum players to equalize the game MMR and skill level and make sure its not an uneven match.