Steps to reproduce:

1. Create a scene using Create -> HD Template Scene. Open the scene
2. Create a new Textmesh PRO (TMP) 3D object and new TMP UI object
3. Create a new material with shader type set to TMP/DistanceField (Surface) apply it to TMP 3D Object
4. Select TMP UI object and set the shader type of its default material to TMP/DistanceField (Surface)
5. Observe broken shaders in both instances

Expected result:
Working shader with HDRP

Note:
Judging from the https://forum.unity.com/threads/distance-field-surface-not-working.622234/ response Distance Field (Surface) is broken for SRP and not HDRP specifically.