The scale of what you just described is really goofy.

The word you're looking for is "big". As in, it embiggens the noblest spirit.

I don’t think it’s feasible to protect a mars-diameter disc of massive magnets from damage by either normal objects traveling through the area or from some human engineered attack.

It's also not possible to protect the ISS from either of those and yet it's operated fine for 30 years. You do not need every little bit of it to be perfect, you just need to deflect enough solar wind that it allows Mars atmosphere to build back up which is what provides the real protection.

If you’re imagining the capacity to create such an emplacement, don’t you imagine that such phenomenal effort and wealth of resources would be better spent solving some terrestrial problem?

Like I said, we waste more resources than that all the time. I'd rather we didn't build yachts and country clubs and private schools, yet we do. There's no reason to not get started building that array, especially if it will take a while.

There’s a real difference between e-waste, which is mostly byproducts of the petroleum refining process with electronic components smeared liberally on, many of which rely on petroleum byproducts themselves and electromagnets, which are, at the scale you’re discussing, massive chunks of metals refined, shaped and organized into configurations that will create magnetic fields when dc is present.

That is not what e-waste is. E-waste primarily consists of silicon chips and the metal wires connecting them. Even the circuit boards themselves are primarily fibre glass, not petroleum.

And no, we wouldn't be creating those using actual magnets, we'd be using electro magnets, which is just coils of wire connected to PV and logic chips.

I quite frankly flat out do not understand why people on the left are so against space exploration suddenly. You know that Elon Musk is not the only billionaire right? And you know virtually that all of them just sit on their wealth, and do nothing with it but wast on luxury lifestyles for themselves right? Yeah it would be better if billionaire's did not exist, but as long as they do, why are you upset about their money going to space exploration as opposed to just yachts and $20,000 a night hotel stays?