Is endless online debating truly improving your faith?

Assalamu alaykum, I have a brother who spends most of his free time on forums and listening to debate podcasts. Much of it is about proving others wrong: Muslims vs. Christians, Sunni vs. Shia, arguments with people who reject some hadiths, always discussing what’s haram... I get it, learning about Islam, defending the faith when needed, and seeking knowledge are good. But when does it become unhealthy or even harmful? For instance, he sees someone with tattoos and immediately wants to argue that tattoos are haram. And I think: okay... then what? Why does every interaction turn into a chance to correct someone or prove a point? What bothers me more is that the essence of Islam seems lost. Good character, humility, mercy, guarding the tongue, helping others, self-improvement, prayer, charity, kindness-these seem far more important than spending hours arguing with strangers online about minor or divisive issues. I asked him why he spends so much time debating online, and he said it helps him "better his deen" and makes him feel good about himself... That last part made me uneasy. If religious debates make you feel superior because you think you know more than the other person, could that feed arrogance instead of strengthening faith? Is there anything in Islam about excessive arguing, especially when there's little benefit? Should seeking knowledge look like this? And how can I advise someone like this without being judgmental myself?