Well I agree with the reason behind the change but not so cool with how they decided to change it.
Reason: Grens have 16 damage per model(4 kars and 1 g43). Meaning on approach when single models stays more front all 5 of the gren model targets and fires at it and immediately kill it(high acc of guns + g43 has very fire rate on top of being even more accurate) this resulted in elite cqc infantry(who are also doctrinal and are more expensive) being sniped to death on approach. This is exactly what made pre-nerf 5 man sections OP as hell.
I also agree with the reason behind the change but not with how they decide to change it.
In COH 1, The system they had in place was a bit complex but it worked. Essentially all Infantry was placed into certain armor classes. There was I believe 6 Armor classes (Been a number of years since I played COH1)but essentially you had Infantry, Soldier, Elite, Heroic, Airborne and Sniper armor types. Essentially this allowed a system where certain units where strong/weak vs other units based on what type of armor that they have.
For example a Mortar could do say 100% damage to regular infantry while against Team Weapons (the things its supposed to counter) it would do extra damage.
At this point in the game it would be too late to add a system like this into COH 2 but what we can learn from this system is that you can/should tweak units based on unit matchup rather than apply broad buffs/nerfs that have unintended consequences that create further balance issues down the line.
Here is how a typical COH2 balance issue plays out as an example:
-OKW Volksgrenadiers struggle vs Maxim Spam.
-Community Agrees Maxim Spam is a problem
-LEIG gets buffed to deal with Maxims while Maxims get nerfed at the same time
-Maxims become useless and cannot fulfill its role, then LEIG turns into ranged sniper with suppression and gets spammed where it rains death and no single infantry squad could survive if they stopped moving for 0.5 seconds.
So rather than create a situation like that, looking at COH 1 system, it would be easier to simply just add a modifier to LEIG. Say a random number like 20%. So LEIG does 20% more damage vs Maxim, it gets tested and seems to work well/adjusted to the proper number. Now OKW can deal with Maxim Spam without a nerf to maxims and without making LEIG into ranged terminators.
Anyway back to Grenadiers. Grenadiers usually fair well vs Soviets. It is USF/British that they struggle with. Rather than come out with crazy upgrades like the 5 Man Grenadier and then nerfing it into the ground when the Units are able to take out more expensive call in units, it would have made more sense and be better overall if Grenadiers instead got say 15% (any suitable number) damage buff or damage resistance buff vs just Rifleman/Infantry Section and adjust the number so that each squad is fairly even in terms of performance/cost.
By creating a band-aid upgrade (5 man grenadiers) to help solve a problem, they ended up creating more problems when higher end units and even Machine Guns get death looped when charged in the front.