Reiterating this. A badly seated ram stick or completely fried ram stick can prevent a computer from booting (has to do with circuitry and power. I'm not an EE major so I can't go into fine detail. But basically, the computer knows the signals coming back doesn't make sense so it yells at you and doesn't boot). But sectors of a ram stick can be damaged and still boot. I've personally had, in addition to hearing stories about people, adding new ram sticks and coming up with odd number for total ram.
An OS reporting out of memory is usually just ram. Bad sectors on the hard drive will usually lead to disk io read/write errors.
But really, the easiest this for this person to do is to just check his own ram usage. Rather than have us guessing the near infinite possibilities that can cause this, he just need to check what his ram usage is like and see what's going on. For all we know, he could be bitcoin mining or running an AI model or running a dozen bots on his machine while running this game. It takes very little to just look at what your computer is doing rather than asking for strangers on the internet for a possible quick fix to a problem that doesn't exist and waiting a day or two for a response.
With that said, on Oni's patreon, there have been some reports of out of memory errors. But, according to Oni himself, every time he asks for more info to troubleshoot, they never reply.
The first rule to asking for free tech support on the internet is provide details upfront. Don't just got "I've got a problem" and provide nothing else. You wouldn't walk up to a mechanic and go "Car's busted" then walk away. You wouldn't call a plumber and go "Pipe's clogged" and walk away. Don't think the tech people on the internet will react any differently. If you're too lazy to do that, than you're also too lazy to get help. Simple as that.