It seems you agree with me that Stock grenadier are bad at attacking and that is part of the reason why AsG and Ostru are used.
No. I'll have to explain cause you just want a simplistic generalisation as saying "Gren bad on attack".
It seems to me you are avoiding topics you don't like to answer to. Simple questions:
1-Do you think stock grenadiers are fine for anything other than 1v1?
2-Have you check how people are playing with OH through the 2v2 tournament?
Let's start by realising the greatest strength for OH on 1v1 is the T2 timing.
Against Soviets, Grenadiers stock can match any stock Soviet opening. But why go even if you can pull ahead with doctrinal infantry openings or gamble for a fast T2.
Against UKF/USF you can't match 1on1 squads and rather than sitting and playing a long extended T1 opening like old days (3/4 Grens, snipers, MG42) you do the same as with Soviets going for doctrinal opening and transitioning to T2.
Osstruppen are not good at attacking, but they will force you to take some time to dislodge them and either you spread your forces or you will be losing map control. In spreading you can use PG/222/FHT to attack lone squads.
Grenadiers can push/attack fine, but not doing so in a way that they won't lose map control or spending resources which are better spent at that point in the game on other things (medic, teller, FHT, etc.)