Ignoring the "how impossible is it to drill 0.2nm holes in anything" conversation above for a moment, what do you get out of stainless steel? My gut tells me yo

Ignoring the "how impossible is it to drill 0.2nm holes in anything" conversation above for a moment, what do you get out of stainless steel? My gut tells me you're looking for something with more permanence, but even stainless steel seems like a bad choice for something whose job requires constant contact with salt water (ergo, rust)