sqlmesh quotes parameters in ALTER SESSION SET for Snowflake is illegal syntax.
What’s worse, it is even used in auto-generated queries. This is what I found in the logs:

2026-01-15 16:35:07,526 - ThreadPoolExecutor-30_0 - sqlmesh.core.engine_adapter.base - INFO - Executing SQL:
 /* SQLMESH_PLAN: 1f393dd1a70d447e851739fbfeddd4b2 */
 ALTER SESSION SET "TIMEZONE" = 'UTC'

ALTER SESSION SET "TIMEZONE" = 'UTC' is invalid SQL syntax for Snowflake.