The first video shows 770 manpower and 5 fuel (two penals, one scout car) beating 480 manpower (two grenadier squads). If you want to count the pioneers you can up the Germans to 680 manpower, but pios here just loiter around and don't contribute to the fight. Furthermore, Soviets had the terrain advantage, one of the grenadier squads was already at around 75% health when the video started and the other grenadier squad took its sweet time to approach the combat meaning most of the fight was one squad at a time, which is of course significantly easier.
The second video shows 690 manpower, 5 fuel and 60 ammo beating 480 manpower. Again the fight was against one squad for a long time.
So M3 is not useless. But is it cost-effective? Do your videos demonstrate anything other than that you can decisively win any engagement when you have a 60% manpower advantage, use good micro, while the enemy units arrive staggered? You might as well show a video of 5 conscripts winning against three Grenadier squads and then claim "this is how you use conscripts".
No. Fuck that. The point is not that Soviets cannot win. It never was. It is that they consistently need to concentrate more manpower in a single place than Ost opponent in order to win. This translates directly to the statement : Soviet units underperform for cost.
See also: the Relic officially recommended counter to Assgrens (two Conscript squads leapfrog-kiting) and Piospam (shock troops in a Scout car).
Again, noone is arguing that M3 has no utility on the battlefield. If anything, this video reinforced my opinion that a garrisoned M3 is the most reliable thing Soviets have to reverse the usual long range equation i.e. force Ost forces to advance from cover.
Yeah, use more manpower to win, thank you, Comrade Obvious
You learn 3 > 2 in elementary school, don't you?