In very simple terms, it means that something is changing state so impossibly fast (“on a quantum level”) that we can’t tell what exactly that state is besides at the instant we check it. Exactly is doing a lot of heavy lifting here, because we can have an idea or an area, but not exactly. What that means in turn though is that by checking or measuring that state, we have interacted with it, therefore making the state we measured no longer valid for what it currently is now, or at rest.

Think of it like taking a measure of a water droplet, in the middle of a lake. You can say “there it is, those atoms are in that droplet and theyre this hot”. But the drop you measured is constantly mixing with the water around it. Sure, you measured the temperature of those atoms in that droplet, but if you try to measure it again you could get a different result. (It’s not a perfect example, but it gets the idea through)

Using your programming model, think of it like reading memory in memory that is shorting out. You can read it once, but there’s no guarantee that it will be the same value again next time you read that bit, because it’s in constant flux.

Yeah VGA is still pretty much gold standard for supportability in my experience. It’s like a console port with baud rate settings, worst case scenario those two should always work.