diff --git a/esphome/build_gen/arduino8266.py b/esphome/build_gen/arduino8266.py
index 8fad93ae2f..fd561078b4 100644
--- a/esphome/build_gen/arduino8266.py
+++ b/esphome/build_gen/arduino8266.py
@@ -744,9 +744,9 @@ def write_project(paths: InstalledPaths, ccache: str | None) -> bool:
     config = _resolve_build_config(flag_defines)
     esp8266_data = CORE.data[KEY_ESP8266]
     board = esp8266_data[KEY_BOARD]
-    # The only in-tree rejection until the native-toolchain validator
-    # (_validate_native_toolchain, final PR of the chain) gates boards at
-    # config time; CONF_BOARD itself is a free-form string
+    # Config validation (_validate_native_toolchain) already gates boards;
+    # kept as defense-in-depth for direct calls, since CONF_BOARD itself is
+    # a free-form string
     if board not in ESP8266_BOARD_BUILD:
         raise EsphomeError(f"Board '{board}' is not supported by the native toolchain")
     board_build = ESP8266_BOARD_BUILD[board]