Piracy: ꜱᴀɪʟ ᴛʜᴇ ʜɪɢʜ ꜱᴇᴀꜱ

I don't think you understand at all. Mockups are assets for graphic designers to display their design work, they aren't the designs themselves. To create mockups it requires a specific knowledge of 3D programs that most designers don't have or are taught in school, or don't have the physical resources to create them at the time.

No, I'm not looking to profit off of this because that would be highly illegal and stupid. Using these mockups in a commercial setting without a license is asking to get a legal notice and sued.

It's for displaying portfolio work for presentation to employers. I'm not profiting off of them at all nor training an AI model to do graphic design. If I were doing that I wouldn't be asking and I'd simply be using the vast library of shitty AI programs to get a crappy generation going.

If I design a poster and want to contextualize that poster in a space, I would use a mock up, except all the free mock ups available online are either bad or don't present the work in the way I want them to. I don't think it's a moral dilemma like you're suggesting.