If accurate, it would be a really stupid design flaw, which isn't surprising. But the jest of its saying is accurate, that storing ammo inside the turret is a bad move.
I'm not so sure I'd call it a "stupid design flaw," considering it's been in multiple generations of soviet tanks and beyond, and these are generations of soviet tanks that have caused western designers and theorists to shit themselves and build counters to them. I'd call it more a design priority, as it's definitely something with a severe trade off against crew safety.
This is a picture of the ammunition carousel below the autoloader, which is directly below the turret, that is rather similar across Russian tanks. It's accurate to say that it's extremely dangeous in the event of a penetration (and sometimes outside of it- the T-64's early autoloader was infamous for its poor ergonomics resulting in it sometimes trying to stuff the gunner into the breach rather than a shell)- slavshit tanks have thrown their turrets for decades, but there's other factors to consider, such as that Russian tanks are actually quite a bit smaller than Western tanks, and thus harder targets, and that the ammunition has to be arranged that way for their autoloaders to work, which is the main component of why they have such a smaller profile.
Seriously Russian tanks are fucking tiny, it was an active part of the design process to make it so they were smaller and lighter while having a similar or better level of armament and protection, so that they can utilize infrastructure heavier western tanks cannot.
Compare the ammunition stowage on a T-72/T-90 to that of, say, an M1 Abrams. You might have noticed from the earlier picture that the M1 has a far larger turret than the T-72. That's because it stores its main gun ammunition in a bustle with blowout panels to redirect any ammunition explosion upwards, with an armored door between the crew compartment and ammunition storage. This makes it a far safer tank in the event of it being hit, suffice it to say, but the tradeoff is that you have a bigger target because the whole damn thing is bigger. The Leclerc tank also has its ammunition storage in a rear turret bustle, but has an autoloader instead of a manual loader.
Of relevant note is the Leopard 2's ammunition storage- while there is a standard rear turret bustle as is normal for western tanks, extra shells have room for stowage in the front and center of the hull. This resulted in rather ugly surprises when the Turks used theirs against Kurds equipped with modern anti-tank missiles.
This is all rather a moot point if one considers that the standard situation for any tank is to not suffer a penetrating hit, for its armor to do its job- so that it really couldn't matter less where the ammunition is because it's not supposed to blow the fuck up and send a different part of your body to fifty different parts of the country. Thus, priority in design would be if the ammunition is placed in a way as to be conducive to getting it in the cannon and firing as quickly as possible, rather than planning for it to be hit and exploding rendering the vehicle combat incapable anyways. Of course, armor protection is just not good enough against weapons like Javelins and NLAWS- they're top attack weapons, hence the prevalence of penetrating hits to the center mass of the tank, resulting in turret tossing. That's a discussion for another time, but to keep it brief- I think the most educational effect this war will have on armor technology is that not having hard-kill active protection is no longer an option against any military with modern top-attack capable anti-tank equipment.
TL;DR the Russians care more about slinging shells than not slinging crew so it's not of concern to them.
