Speaking of artillery… Have you actually seen the locations totally bombed to the ground before Russians move forward another few meters. No amount of mining with anti-personal mines would survive that well enough to actually deter soldiers.

Artillery is actually surprisingly bad at clearing minefields. If you could just lob shells onto a minefield, why would nations everywhere develop incredibly expensive mine-clearing systems?

Minefields are used because they work. Mixed minefields are used just like castle walls, to slow an enemy and increase the defender advantage. They don’t stop an enemy by itself, but purely anti-vehicle fields are easily cleared by hand, or walked across. Mixed fields are not.

Actual infantry movement (the reasons I refered to “marching”) that would make anti-personal mining reasonable doesn’t exist anymore

Minefields that deter strategic movement have never existed. They have always been a tactical thing, even in WW2 desert combat, which saw some of the most extensive minefield ever, they have always been tactical obstacles.

Mining the border doesn’t mean spreading mines across the entire literal border. It means defending key areas with thicker fields, and probably not even that, it means keeping them ready just in case.

The thing is, yes, mines might kill civilians some time in the future. But losing a war against a genocidal foreign country will absolutely kill more.