Anyone else play in high rank with friends but struggle in low rank with randoms?

I didn't start playing ranked until recently. So I'm way behind the curve. I'm currently mostly through gold and find games incredibly difficult to win or even place well enough to consistently rank up. I only play in Gold rank when alone since all my friends are beyond there.

But then I'll play Plat or Diamond with my friends and do just as good if not better than them and consistently get games where we each have 3-4 kills and 1200 damage and place second.

What's going on here? How can I be more productive in my solo games? I don't want to blame randoms because it's not like I'm doing well enough to carrying them, but I can definitely tell there is a significant skill gap between me and my teammates and enemies and even then I can't progress. I just feel like I play better against better players.