Beyond the obvious stuff like installing an ad blocker, I don't know. The best idea I've seen is what you already said, just limit access to funds. When my dad

Beyond the obvious stuff like installing an ad blocker, I don't know. The best idea I've seen is what you already said, just limit access to funds. When my dad went through Alzheimers, we canceled his cards through the bank or let them expire and just never told him. But he was far enough gone that he would never have had reason to buy anything anyway so he never noticed. For someone still functional but easily tricked and unreceptive to the idea of limits, I don't know.