Serious question:
How come? Penals and sniper openings have been the meta for what feels like ages until Conscripts got their 7-man buff. And at least in the early game, not much has changed on the Axis side. Volks got a mini nerf, Sturmpios a very small combat buff. Grenadiers got a vet3 buff but that does not affect the early game.
PGrens come earlier now, that's probably the biggest new thing in Axis early game, plus Panzerfusiliere are now (compared to 2-3 years ago) viable although we do not see them in every game anyway.
Throughout all those mini changes, Soviets have been a quite competitive faction, regardless if they were using Penals or Cons. And judging by tournament games we had since the 7-men buff, Penal builds are less abundant but still played and also still competitive. So it's at least not as a clear case as you make it out to be.
I'd rather argue that Conscripts have become so cost efficient especially in the late game that they just beat Penal build. Especially considering that T1 builds need to back tech at some point while T2 build do not.
You are looking at things in isolation, without considering what each openings achieves/tries to do and the meta around that let them shine or not.
1- Penals vs Cons. They achieve completely opposite effects.
One relies in pure brute strength early on which fells short as the game goes on. You sacrifice map control in favour of finding isolated targets to force retreats and then trying to snowball from that position.
Cons are the opposite. You get map control, you can stall with sandbags and are more efficient in the late game, specially as snare units. You get the added benefit of merging early on flamers. As you mentioned, you also save money and time in T2 as that's your natural tech progression.
2- Penals strats are not ideal against OH, specially in the current meta which absolutely demolishes as it punishes SU early mid even harder.
OKW has historically been the main use of Penal based strats, and less people play them.
3- Penals based strats require the faction to rely on "hero" units to carry later on. Either mass T70 based strats or late game units like IS2/KV2. When OH consistently gets to put pressure delaying T70 or accessing T3, and OKW doesn't feel the need to go mechanized "all in" with P2/Puma, more in favour of BHQ with Flak/fast transitioning to PIV, the strat is less effective.
4- Sniper strat is awful against OH meta and high risk, mid reward against OKW. Clowncar strats have generally been only great against OKW and everyone has a pocket PF just in case to counter it. Sniper was only meta during GC2, with OH been mostly Mobile defense. We didn't see snipers during heavy meta.
At this point i think i need to disclaim that this is mostly on 1v1. Sniper can still be used on 2v2.
It's not that T1 openings have become useless or non existent (such as maxim spam), it's just that it has become even more niche or become a "pocket" strats that only works in specific situations compared to bread n butter Cons + T2.