More likely: A small amount of the leaked hydrogen encounters an ignition point, igniting the primary mass.

The ignition zone is larger, risk is higher.

Pure hydrogen can’t burn without oxygen, so you generally get a tiny flare and then a flame based the size of the crack. It’s really about the same risks as using gasoline which almost never causes a significant detonation.

With vehicle, heating, rocket, or aviation applications, quantities involved are nontrivial. Hydrogen's flammable and explosive ratios with oxygen are large, and contrast starkly with other fuels; kerosene (jet/rocket fuel), bunker oil, and deisel, which ignite with difficulty, petrol, which ignites readily but not explosively, and even natural gas which deflagrates rather than explodes under most circumstances.

Add in hydrogen's extreme tendency to leak, metal embrittlement, and high pressures and/or low temperatures, and the risks are immense. Particularly at scale, in widespread use, with poor maintenance and inspections.

It’s technically explosive in many situations where the location or net energy released makes that irrelevant. Being significantly lighter than air you might hear a loud bang above the vehicle where gasoline’s foof ends up being significantly more deadly.

It’s not strictly better or worse, just different. Diesel for example can be very dangerous in a large open topped container, hydrogen just doesn’t stick around in that environment.

PS: Consider what it would take to make a large hydrogen fuel air bomb that’s as effective as it’s hydrocarbon equivalent.