No, no it doesn’t. MM doesn’t care about your SR.
It’s literally the exact same system.
Read: How Competitive Matchmaking and Rating Works (Season 26)
You can literally be in a GM game and have <500sr if you take the time to deflate your SR with leaving games with the -10sr cross-loss.
If you were matching based on sr then above plat you wouldn’t have developers saying “Your SR will decay but you will still be matched with people of similar skill”.