Use WithNullability instead, since it's more descriptive of what we actually want and futureproof

src/Features/CSharp/Portable/Completion/CompletionProviders/ObjectCreationCompletionProvider.cs

@@ -78,9 +78,9 @@ protected override (string displayText, string suffix, string insertionText) Get
                 return (symbol.Name, "", symbol.Name);
             }
 
-            if (symbol is INamespaceOrTypeSymbol namespaceOrTypeSymbol)
+            if (symbol is ITypeSymbol typeSymbol)
             {
-                return base.GetDisplayAndSuffixAndInsertionText(namespaceOrTypeSymbol.WithoutNullability(), context);
+                return base.GetDisplayAndSuffixAndInsertionText(typeSymbol.WithNullability(NullableAnnotation.None), context);
             }
 
             return base.GetDisplayAndSuffixAndInsertionText(symbol, context);