@TheTao what exactly are you suggesting is incorrect - the V8 memory cage or the V8 documentation?
That looks like the OS level (Windows?) task manager reporting 8GB for the whole process.
That means it reports total process memory. The 4GB limit is the heap that’s accessible to user memory (aka JS object cage or V8 memory cage - Electron and the V8 Memory Cage | Electron) - i.e. what Obsidian can allocate.
Naturally, in order for user memory to be 4GB, the VM needs to allocate in addition to that to operate, so that’s why you’re seeing a difference.