It's all true - mg42 is only better at suppresing large groups from my experience - don't feel bad about what you saw. All allies mgs are better in 1v1 against 4 man squads than mg42 is against 5,6 or 7 man squads. People evaluating mgs often forget that their mgs are used against 4 man squads and mg42 shoots at bigger squads.
Another reason why allied mgs are better in 1v1 is that they pin a tiny bit more slowly. Pinning enemy quickly makes the pinned unit take less damge. So when an mg42 quickly pins a squad, such squad has lost less health and can stay under fire relativeluy long. Because these squads are 5,6 or seven models, it means that they have more health, which makes it possible for them to stay under fire longer (in coh2 each model has exactly the same amount of health irrespective if it is 4,5,6 or 7 man squad). They way damage is distributed when under mg fire also helps as damage is more or less evenly distributed for each model. This means that you will more likely lose health than models, which means you won't bleed much manpower staying pinned for relatively long. When retreating after relatively long period you are likely to need healing more than reinforcing. Since healing is free you won't lose much even when you have stayed under mg42 fire for quite long (enough to flank it etc.)
Allied mgs, however, pin units more slowly so they deal quite a lot of damge to them before the unit gets pinned and that's why allied mgs often manage to kill a model on an ostheer squad before pinning it. The fact that ostheer infantry is mostly 4 models means that it has less health. Less health means that the unit will stay under mg fire for a shorter period of time. Both dealing more damage before pinning the squad and the fact that ostheer squads are 4 man means that allied mgs are better. Allied mgs force ostheer squads to retreat much more quickly from their arc than mg42 makes allied infanty retreat from its arc. Also as ost you are way more likely to lose manpower (models) attacked by allied mg while mg42 will mostly drain health from allied squads.
Thank you for sharing in details i cannot express better. In my experience, all this is very true.
It is easy to just wave off mg42 as bestest just seeing the specs of bigger arcs and pinning inside arc. Or simply adhereing to old, outdated impressions when mg42 was very good against units it needs to handle.
But tiny details and changes as above only can be experienced in game when it faces off against units available.
I stand by my point the 50cal is the bestest mg today. Instant teardown, fastest setup, strong suppression, ap ammo, high models kill ability.
even vickers does better than mg42 in ukf vs wehr...faster tracking, slightly farther range, more deadly in killing models, 4 v 5 models.
mg42 simply needs some vet buff to keep up as allies infantry scales upwards.