Ray Tracing crashes the game every time it is used except after the very first time (RTX)

Ray tracing works in the first session after installing Preview 1.26.70.20. In every later session the game
crashes moments after joining a world with ray tracing enabled, or after switching to ray tracing in-world,
just before terrain renders. Reinstalling the game and clearing the NVIDIA and DirectX shader caches does not
fix it. Several other users have reproduced it.
Steps to reproduce:

1. Install Preview 1.26.70.20 on an RTX-capable PC.

2. Launch, enable Ray Tracing, join a world. It works.

3. Close the game, relaunch, and join a world with Ray Tracing enabled (or switch to Ray Tracing in-world).
   Observed: the game crashes as terrain starts to load.
   Expected: ray tracing works in every session, as it does in the first.
   Technical details:

• Access violation (0xC0000005), read of address 0x0, at Minecraft.Windows.exe+0x3239FD3
  (1.26.70.20, timestamp 0x6AC93F61), on the "Render Chunk Build" worker thread.
  Same offset in every crash (10+ crashes).

• Happens with the stock game and default files; no heavy resource pack or setting changes required. Just any world or resource pack to enable ray tracing.