No, it’s not a bad idea at all.
Having a credit card is a good idea. Having half a dozen credit cards is a great idea. You’ll never run out of money in an emergency.
What constitutes an “emergency” can vary from country to country e.g. hospitalization is covered by insurance in some countries, so it’s not an emergency there; but it’s not covered by insurance in some other countries, so it’s an emergency there.
Notwithstanding the definition of emergency, I’m sure there are emergencies in all parts of the world.
It’s revolving your credit card outstandings and incurring usurious rates of APRs that’s a bad idea.
PS: I’m not even going to talk about legions of startups founded by using credit card as a source of funds.
PPS: Many people who propose cashless alternatives like a Debit Card / Venmo / UPI / BHIM etc. as a better alternative to credit card miss one thing: These alternatives let you spend only up to the balance in your bank account. Many emergencies entail amounts well above a sensible bank balance. (I’m aware of ways by which you can spend more than your bank balance via debit card but they come with exorbitant overdraft protection charges).