Statistically gas cars are still much more likely to catch fire than an EV. The issue is that when an EV does go up in smoke, it's much more severe. And naturally gets more press coverage. In an enclosed area such as shipping container, with other combustible sources (e.g., large batteries, gasoline), it's not going to be pretty.
If either vehicle catches fire in your garage at home there are more than enough "fuel" sources for the fire to cause some serious damage. Which is why I keep fire extinguishers, cameras, and other smart sensors in my house/garage to detect for such an incident. Regardless of whether I happen to have an electric or gas powered vehicles.
Also, be sure to keep up with recalls on your vehicles!