3. The engineers might be a bunch of former crypto dudebros who design futuristic looking stuff, overstate the specs by about 1000%, but couldn't design their way into using a knife and fork properly. If you follow the videos of AdamSomething, you'll know that this is not exclusive to Russia. One of the most spectacularly ridiculous designs for an aquatic Galt's Gulch looked like a toilet until they put structures on the outside (which would snap off in the first storm) to make it look like a tortoise. Check out some of thse stuff over there, it makes Musk look rational.
4. The engineers were spot on and came up with good designs that had a chance of working until higher ups decided to skim their money off by eliminating redundant systems that would keep a half billion dollar piece of war kit working no matter what while keeping the estimated price the same. Then production took over, everybody at every level simming their money off the project by reducing the thickness of steel components and adulterating others. You now, like adulterating the rubber for trhose viatally important O rings with powdered asphalt or soot or just try9ng to cut them out of old truck tires. That could explain why the last missile blew up in the hole, taking the whole test facility with it.
5. Putin. He's so lost in magical thinking that he thinks this stuff is fully operational, that's why he still thinks he's going to win someyhing besides the long term destruction of Russia as he keeps slaughtering his working class..