What do I do if my AirPods went through the washing machine and they turned on right after but aren’t now?

You don't say which version of AirPods, but for most variants their water resistance is suitable for tolerating usage in a rainy environment, or sweating in a workout. This is nowhere the intensity of water exposure they would get in laundry, even without the additional damage and increased corrosion by hot water and detergents.

I think your AirPods are almost certainly destroyed, and the best solution will probably be replacement with new AirPods.