You do not need an MMR reset for that, especially if you think that you belong higher than where you are.
Just buy an alt account and you will be placed in Gold immediately, There you have it, a higher SR than where you currently are at.
The question then remains whether you can keep it or not.
I created this account to learn different support heroes, than the ones on my main, and slowly started to make this my main account. I place Gold and went down to Bronze because I could not play Mercy at a Gold lvl. I climbed from Bronze to Gold with Mercy while learning her and also picked up on a lot of other things I was unaware of, like general gamesense. I learned, I improved, I ranked up.
I can tell everyone here that I think that I deserve to be Plat or Diamond and ask for an MMR reset so I can be put there, because my teammates are keeping me down, or I can just go and buy a Plat or Diamond account and see how well I do there.
Also, worth mentioning, playing in a non-comp environment, that is scrims with and against better players than you will not do a lot to help you to overcome the issues one experiences in a solo Q Comp environment. I have no doubt that I can win games while playing with a Diamond team, but that does not tell me that I am Diamond, it only tells me that they are carrying me, have noticed that I am not up to par and they are babysitting me and telling me what to do. I have no idea how Diamond games are being played, since I never played in one, but I do not know that they are played completely different than my Gold games.
People’s inability to adapt to general things that plagues their elo is the reason why they are not ranking up. I see no reason why you would flame your Ana for example for not having the gamesense to heal you or the aim to heal you in Bronze.
If you notice smth like that, you acknowledge it, you move on and you position yourself in a way where there is cover or preferably a healthpack, especially if you are playing DPS. You also cannot go all aggo Rein just because you saw a T500 do it and succeed at it and then blame your team for not following up, because they will not know in Bronze or Gold how that is at that moment the right play even if you call it out because they are all used to never going pass the choke and just sit there and blame everyone else for losing the game.
An MMR reset will not fix those issues. Players will still play the same way they always did and will still continue to blame the same things they always did.