Placing a card down isn't what triggers the loop, what triggers the loop is the position of the monster with the highest attack constantly bouncing back and forth between your monster and their monster who is constantly gaining and losing the Attack Boost of an equip spell.

If you place a monster that already has a lower attack then there is no infinite loop since their monster is the one with the highest attack regardless of whether they have the equip spell or not. Likewise putting down a monster with even higher attack regardless of the equip spell doesn't trigger the infinite Loop because your monster is the one who gets the benefit of pole position.

As for a judge, they should rule in your favor because the opponents entire strategy is to win by forcing you to make an illegal move.