I don't think Task & Purpose should be taken this seriously. There are always few misses in his videos.Its pointless to equip mechanized infantry with battle rifles.Only mountain infantry should have SIGs where their long range can be used effectively.Mechanized infantry accompanying tanks in IFVs need assault rifles and AK is excellent for that.Even assault detatchments of mountain infantry will need AKs.The AK203 is an excellent rifle,the toned down ak12/15 that the russians are adopting is not very different(original ak-12/15 was much different but failed due to high cost and unreliability in russian army trials).Yes,russian army infantry upgradration program is standardizing on AK. SIG is needed for the mountains.Also we cant afford telescopes on 1 milion SIGs.Without scopes you are wasting the SIG.
For example, he says free floated AK. But actually you can't free float a long stroke gun like an AK.