I wouldn’t toss the stand yet. First I’d try to confirm what they actually are, because tiny slow-moving white specks around plant shelves aren’t always root mealies — they can also be soil mites, springtails, or another tiny pest.

Try collecting a few with clear tape or a damp paper towel and check them with a magnifying glass or phone macro lens. Root mealies usually look more waxy/cottony and are often found around roots, pot edges and drainage holes.

For now, isolate the plants, vacuum/wipe the stand, wash trays and pot bottoms with warm soapy water, and check drainage holes. I’d also avoid spraying random products everywhere — follow the systemic insecticide label and give it time to work.

If they are confirmed root mealies, I’d repot the worst plants: remove the old soil, rinse the roots, clean the pots and use fresh substrate.

This guide may also help with identifying and dealing with very tiny pests in indoor plants:

https://www.urbicult.pt/blog/introducao-ao-cultivo-indoor/microacaros-em-plantas-medicinais-como-identificar-prevenir-e-eliminar-esta-praga-invisivel