Should I confront my grandmother’s tenant about his late rent payments?

My grandmother has been renting out a room in her home to a guy in his 30s for the past three years at a much lower price than market rate. She has never raised the rent, and on top of that, she cooks for him (and sometimes his girlfriend when she visits) and even buys food for him.

The issue is that he is always late with rent. My grandmother has to remind him multiple times before he finally pays, and even then, he often delays payment. Despite this, she doesn’t have the heart to stop renting to him or to increase the rent.

I feel like he’s taking advantage of her kindness, and I’m getting frustrated seeing her struggle to get what she’s owed. Should I confront him when I see him? Or is there a better way to handle this? Would appreciate any advice.