deprecate SpanStartOption

CHANGELOG.md

@@ -16,6 +16,11 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Add the `WithLoggerProviderOptions`, `WithMeterProviderOptions` and `WithTracerProviderOptions` options to `NewSDK` to allow passing custom options to providers in `go.opentelemetry.io/contrib/otelconf`. (#7552)
 - Added V2 version of AWS EC2 detector `go.opentelemetry.io/contrib/detectors/aws/ec2/v2` due to deprecation of `github.com/aws/aws-sdk-go`. (#6961)
 
+### Deprecated
+
+- `WithSpanOptions` in `go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc` is deprecated.
+  It is only used by the deprecated interceptor, and is unused by `NewClientHandler` and `NewServerHandler`. (#7601)
+
 ### Removed
 
 - Remove support for the `OTEL_SEMCONV_STABILITY_OPT_IN` environment variable as well as support for semantic conventions v1.20.0 in the modules below. (#7584)

instrumentation/google.golang.org/grpc/otelgrpc/config.go

@@ -215,6 +215,8 @@ func (o spanStartOption) apply(c *config) {
 
 // WithSpanOptions configures an additional set of
 // trace.SpanOptions, which are applied to each new span.
+//
+// Deprecated: It is only used by the deprecated interceptor, and is unused by [NewClientHandler] and [NewServerHandler].
 func WithSpanOptions(opts ...trace.SpanStartOption) Option {
 	return spanStartOption{opts}
 }