Unset log record severity is not INFO

CHANGELOG.md

@@ -20,6 +20,8 @@ release.
 
 - Add optional `Event Name` parameter to `Logger.Enabled` and `LogRecordProcessor.Enabled`.
   ([#4489](https://github.com/open-telemetry/opentelemetry-specification/pull/4489))
+- Remove the suggestion that backends or UI may represent log records with unset severity as INFO severity.
+  ([#4509](https://github.com/open-telemetry/opentelemetry-specification/pull/4509))
 
 ### Baggage
 

specification/logs/data-model.md

@@ -303,6 +303,9 @@ events. Larger numerical values in each range represent more important (more
 severe) events. For example `SeverityNumber=17` describes an error that is less
 critical than an error with `SeverityNumber=20`.
 
+The exception to this is the zero value (`SeverityNumber=0`), which,
+since it us undefined, SHOULD NOT be compared to any other severity number.
+
 #### Mapping of `SeverityNumber`
 
 Mappings from existing logging systems and formats (or **source format** for
@@ -328,12 +331,6 @@ For example if the source format has an "Informational" log level and no other
 log levels with similar meaning then it is recommended to use
 `SeverityNumber=9` for "Informational".
 
-Source formats that do not define a concept of severity or log level MAY omit
-`SeverityNumber` and `SeverityText` fields. Backend and UI may represent log
-records with missing severity information distinctly or may interpret log
-records with missing `SeverityNumber` and `SeverityText` fields as if the
-`SeverityNumber` was set equal to INFO (numeric value of 9).
-
 #### Reverse Mapping
 
 When performing a reverse mapping from `SeverityNumber` to a specific format