If they ragequit AFTER losing lane, then yes.
If they tilted and left over some bullshit before the match even started, then thank your lucky stars that loser isn't on your team and play.
Let me tell you a story:
Jhin/Ori load into a match vs Vayne/Zyra. Jhin disconnects unexpectedly before he even reaches the lane. Never comes back.
So i'm over here under tower with my Coin, doing a shit job of last hitting because I one trick support, just trying to not feed for long enough for my ADC to come back. Vayne tries to towerdive me alone level 3 to my level 2, dies to tower and neeaaaarly kills me.
Now this is before turret plating, and before tower damage was changed such that mages can hurt them more. So they get nothing from me being forced to back. I keep on last hitting under tower and Zyra and Vayne both try to dive me before any of us have hit 6. They manage to kill me, but both die.
Then my jungler shows up and we pull off a double, giving no kills.
Zyra ragequits.
We win the now 4v4 match.
Turns out losing a 2v1 lane sometimes causes tilt. Tilt that straight up lost them the game because their now solo Vayne was actually behind me in level, due to having to share exp.
Would it work in today's meta? Probably not with supports taking
and even a little tower damage yielding gold. It probably wouldn't even have worked if they picked different champions or juggled aggro better. But I honestly wasn't expecting it to work in the first place. You never know until you try I guess.
At the very least, you should try until 15 so that feeding doesn't effect your stats too much. Assuming you don't get to just remake and play a normal match instead.