I'm always surprised to hear that more people don't actually use Siri on their iPhone/iPads. I suspect it has to do with not knowing the voice commands well enough or being burned by a failed attempt to use it.

To help you connect better with Siri, Lex Friedman has a couple of articles up at Macworld that will get you talking to Siri again: Four ways to get things done with Siri is all about setting reminders, scheduling events, texting and taking notes, and Six tips for mastering Siri is an older article that has a good overview of commands you can use with Siri.

My wife uses Siri ever day for reminders, alarms and timers. We'd probably use it a lot more except that either our house (aka kids) are too loud or it's more of a distraction to sleeping babies to use Siri.