Ukraine already violated the treaty and have been using antipersonnel mines, they must just be close to out of USSR leftover stock. Russia not being a party to the treaty have also been using them the whole time. This isn't a very substantial change besides getting Biden's fingers directly in another crime against humanity, dude just loves killing people
Even if these landmines become inert after a certain amount of time there's still a nonzero chance civilians could be killed by them. I knew the US never signed the Ottawa treaty back in the day, but I didn't know Russia has already been using landmines for the last two years of the conflict. I still don't think landmines should be used at all.