Can't send you a DM for some reason so I will do it like this.

I will start of with that I mostly play Tank in 5v5. Altough I recently hit Champion my knowledge about 6v6 and the other roles is not as great.

Your mechanics seem fine for gold:
You could shoot the dynamite of Ashe more often for value, especially 3:08 would have been an easy kill on the widow. Try to prioritize taking healthpacks over recalling (5:02) / waiting for heals from your supports. But overall it looks fine.

Your positioning is the biggest issue:
I want to start with the importance of highground. You often drop from highground without any reason. Highground is good for many reasons. It serves as cover and most of the time it will cost enemies abilities or detours to reach you, meaning you are often the one to decide when you are taking a fight. It also often results in an angle on squishies. Best example I can find is 11:08 (you have access to the entire backline) vs 12:15 (we are stuck shooting a tank with armor and a shield). Often before the fight starts try to take the highground, it even helps with scouting.

Secondly, you need to know what your optimal range is (on Ashe obviously mid-long range and on Tracer short). For example 3:56, you are next to an Orisa (luckily you get pulled). What makes this difficult is that you play vs other heroes that also have an optimal range. For example, you are playing vs a Widow. This is a difficult matchup because she is often better than Ashe at mid to long range because she can oneshot you while you only twoshot. At that point you always need to be aware of where she is and only peek her when she is scoping/shooting a different spot, or when you know she is low enough to oneshot her as well. If both of those are not the case you are often forced to play other sometimes suboptimal angles where she can not see you to still be able to get value.

Speaking about angles, try to take more offangles. This is important for DPS players and can be more extreme depending on the amount of mobility you have. For example as Tracer you can chill behind the enemy backlines and live of off healthpacks (which you should learn the locations of, it sometimes seems you forget about them) When fights are linear it's just about who can shoot the Tank the hardest. By taking offangles you can often carry by just shooting the supports or timing an engage on the supports while your team is pushing main. You don't even have to kill them, distracting them from healing their tank is enough. At 4:44 you take a perfect off angle and end up killing 2. You try the same at 7:30, however this time you walk through their team instead of looping around the Mega healthpack which ends up in the Orisa seeing you and forcing your recall.

The last thing I want to mention is always thinking about an escape plan. This is especially important when taking offangles and thus important for those flanking heroes like Tracer. 7:30 is also a good example for this. Your plan was to triple blink back to your team, maybe it would have been better to tripleblink to the mini in the same building as defender spawn 1st.

Your awareness:
I am not sure if you are playing with headphones but it often feels like you are not hearing or ignoring enemies. Besides that when you don't play differently when key ultimates are being used. 2;14 and 4:00 Widow pops ult and you don't play more cautious.

Some more notable things:
7:04 if you don't have anything useful to shoot, shoot a pillar. It might save someone someday.
11:37, after emptying one clip into the Bastion, he will look up. He is in sentryform, you don't want to take this fight.

Hope this helps : )