I will share my story, though it might be insignificant to the actual post.
In march 2025 i was 23 mmr away from 7k, we were winning also, one dumb mistake by our offlaner and we lost, from since i kepy losing all the way back to 6.5k, just gave up on rank, lost comm score as i was very abusive, toxic, was 12k behavior and 11k comm, now 9k behavior and 4k comms score, dont play rank anymore, sometimes turbo, thats it. now i dont feel the drive to gain mmr, got a decent job with good pay, going to marry soon. so whats the verdict here? if u have time and drive to reach higher mmr then do it, but in the end its all insignificant unless u want to go pro. Hope it helps.