For those who want a TL:DR - embrace tank-killing SPAAGs, ignore community whining about them, undo all old nerfs to their tank-killing ability, make using them against planes in RB much simpler without requiring dozens upon dozens of matches of practice, up their SP costs to medium tank levels like the ZSU-57 already has, increase their rewards for killing planes, and if SPAAG are exploiting issues between new shell models not working right with old armor models, you fix the damn armor models, not punish the SPAAGs!
Detailed Explanation: I personally think adding the belt was a good change, and because the guns actually did pen that much in testing, it is fine.
The problem is the community seeing SPAAG go Ersatz -TD mode and screeching to the heavens, nothing more, simply because they’re angry at being killed by something unexpected. Autocannon light tanks in the same BR range pen almost as much armor or more, have much better mobility overall, better RoF, lower profiles, and in some cases also ATGMs to pen things too thick for the autocannons to deal with. It is complete and utter hypocrisy to allow autocannon IFVs free reign but punish SPAAGs when the latter are ultimately worse at tank-killing than the former when not considering exploitation of broken game mechanics.
Now, do SPAAG exploit weaknesses in Gaijin’s armor models? Yes, they very much do. One of my 9 kills in the nuke game last night was against an angled T-34/85, where I first blew out his barrel and then walked my shots onto the seam between his UFP and LFP, after which one got through and he exploded. A kill like that is frankly BS, and I knew it was BS when it happened. But said BS is entirely the result of not giving every single tank ingame a complete volumetric armor model. New shell model doesn’t interact well with old armor model - who would’ve guessed?! We have known this for how many years now since volumetric mechanics were first added to a handful of top tier machines?
I frankly think that there is no practical difference between an SPAAG and an IFV at the end of the day, and that SPAAG tank-hunting should be encouraged and embraced fully, not punished. We do want people to actually play SPAAG, do we not? Sitting around silently waiting for CAS that may or may not come is boring, and discourages people from playing SPAAG at all. Going and hunting tanks with a rapid-fire buzzsaw is funny, in the same way using a derp artillery gun is. Ersatz-TD-SPAAG are not going away, so why keep trying to fight a losing battle at this point?
Thus, I propose an intentionally contrarian opinion - remove all old nerfs to SPAAG tank-killing ability. If one still has forced mixed belts (Kugelblitz for example), undo that nerf. If one has a forced tiny shell count limit on its antitank rounds (almost all high BR SPAAGs), remove that limit. If one is missing its best anti-tank shell (Ostwind, Ostwind II, all 40mm Bofors platforms, Chinese 25mm, Russian 23mm, M168 Gatling, Russian 30mm on 2S6 & Pantsir, ZSU-57 missing APCR, etc just to name a few I found via a brief Google Search), add it. I am not against raising their SP costs to be equal to light tanks or even mediums/TDs.
I would rather see more people use SPAAGs and actually move outside of their own spawn zones, even if they are focusing on killing tanks. Then at least some will be in useful positions to surprise CAS from when the opportunity arises.
If we’re worried about SPAAGs being ineffective against aircraft due to BRs going up from tankbusting - we shouldn’t really. They already are ineffective below radar tier unless the plane is completely careless or flying headon at the SPAAG. Planes have too much of an awareness advantage compared to SPAAG to be a remotely fair fight - hence why I support giving SPAAGs a short-range lead indicator even in Realistic Mode.
Stock crews get it out to 1km range at most. Aced crews, out to 1.5km. Both non-radar SPAAGs and radar SPAAGs with the radar unit turned off/disabled will have this feature.
It also must be said how SPAAGs are not rewarded well for the times they do kill aircraft - that is just wrong.
Lastly, I see lots of people talking about APHE overperforming - the community vote unfortunately failed to get anything going there. I supported the change to make APHE realistic, but I doubt snail will ever attempt to touch it again. And I’m not even sure if the proposed change even would have fixed the problem of nuclear SPAAG APHE from 30-37mm sizes.