Wallet security for beginners

Hi all, this question probably came up before and I’m aware of the recommendation to keep a cold wallet on a USB drive or on an air gapped computer in an underground bunker, but for the practical day-to-day user is that really necessary? I’m not gonna lie, I store all my crypto in Atomic for iOS and I backup my wallet keys in the notes app. I haven’t had any issues for years. Is this something that needs to change? What approach do you recommend as the best middle ground between security and usability/convenience?