nothing short of a .50 Cal armour piercing bullet gets through those tanks. And even then a chance of an explosion is very very low, it would probably just produce a fire just like gasoline (which can also explode under the right conditions). But that safety requirement is still a barrier, as it raises the cost of an already extremely expensive technology. Personally I can see hydrogen catching on for some niche applications, but for every day driving I don’t see the price ever going low enough for it to make sense compared to electric.