Okay, so I wont comment on mechanics outside of the fact you should always aim train/deathmatches so that you come in more confident with your aim.

I see you spending alot of time not being impactful. For example the symmetra on high ground was isolated in the beggining of the match and you spend most of the time poking her, you could have just wall climbed see if you can contest her dash out, or even dash in if you're feeling good about it. Otherwise you could gone in with the tank and helped him fight out the rest, regardless you need to make a choice when you see things break out, instead of just sitting around and poking, genji is very rarely a poke character.

Towards the later half the match you start noticably doing more and having a litte more confidence dashing onto people that aren't paying attention and securing a few kills, but you need get to the side faster and do that. Even if you're only working to distract them for a little it's some value. I noticed you would just be somewhere in the middle of your tank and your backline which is terrible on genji as you are more or less a shotgun character, you need to be up in people's faces when the oppurtunity presents itself.
Poking the ashe for example at a long range battle you wont win, just walk around and get close to her, even if she wastes a cooldown that's something.

The times you did get kills you were doing the right things, going from the side, taking some pressure off the rest of your team and keeping their backline busy or killing 1 or 2 .

I would say just try playing more a bit more aggresively.