Isn’t it that because you get higher and you get 50/50 vs better players. Having 50/50 at 1500 cr and 2700 cr are two separate things.
About what was said about Dota 2 it works completely different as it works based on two things mmr (which is our rating) and behavior score. More reports you get more toxic people you get with solo queue. It means that if you get reports you will play with tryhards only picking carries with no support, stealing farm, sending boots in 3 parts to other lane when you’re mid etc. So it’s not worth tryharding. Less toxic people have easier time getting mmr. Youtuber Dota 2 Bowie made an experiment. Played on account with 8000/10000 behavior score below his mmr and he got 7/10 wins and then on one with 2000/10000 and he won only 2 games.
Genious right here this is probably the best idea i have heard, you could even have different difficulty of bots to practice against. I know when i first started playing lol wayyy back and i was to bad to play normal games since i was so new and got flamed basicly every game loosing and having teammates be mad at me. Then i found bot games and from there on i just practiced against them and got a lot better quickly. For me the worst part about being new to arena is that you have no idea where to start unless you have a friend to help you.