I wouldn't trust them but so much...
Just like I would not trust older vehicles with old school gas tanks, no gas shut off ability and or older vehicles with extremely poor has tank placement.
If you think a battery is indestructible...
Try taking one and having it hit a large tree at 55 to 70 mph. Think they don't get exceptionally hot ?? Take your wrench and connect your starter battery terminals in your car and see and feel what happens.
Now that is no where near the heat and energy put out by a ev battery that has far, far, far more stored potential energy vs a simple starter battery
But I would trust a newer gasoline powered vehicle over a EV one. In a high impact accident.
Again. . . The solid state lithium ion batteries could potentially be far, far, far safer and more stable by a whole, whole lot..
This would be equivalent from going from 1970s carburator gasoline powered vehicles with extremely simple gas tanks, gas lines and no ability to shut off in the event of a major impact... To a early to mid 2000s vehicle with greatly upgraded gas tank, gas lines, good gas tank placement and an electronic system designed to shut off gasoline in the event of a major impact.
Gasoline fires were common in Nascar accidents all the way through the 50s, 60s, 70s, 80s, 90s.
What changed ??
Better fuel cells and the ability to shut off gasoline delivery electronically in high speed wrecks.
Solid state lithium ion batteries could potentially be that huge of a game changer.