return a simple bool for uncomparable data

astropy/table/table.py

@@ -3699,7 +3699,11 @@ def _rows_equal(self, other):
 
         This is actual implementation for __eq__.
 
-        Returns a 1-D boolean numpy array showing result of row-wise comparison.
+        Returns a 1-D boolean numpy array showing result of row-wise comparison,
+        or a bool (False) in cases where comparison isn't possible (uncomparable dtypes
+        or unbroadcastable shapes). Intended to follow legacy numpy's elementwise
+        comparison rules.
+
         This is the same as the ``==`` comparison for tables.
 
         Parameters
@@ -3740,12 +3744,12 @@ def _rows_equal(self, other):
                 # numpy may complain that structured array are not comparable (TypeError)
                 # or that operands are not brodcastable (ValueError)
                 # see https://github.com/astropy/astropy/issues/13421
-                result = np.array([False])
+                result = False
         else:
             try:
                 result = self.as_array() == other
             except whitelist:
-                result = np.array([False])
+                result = False
 
         return result
 

astropy/table/tests/test_operations.py

@@ -2468,7 +2468,19 @@ def test_mixin_join_regression():
 )
 def test_table_comp(t1, t2):
     # see https://github.com/astropy/astropy/issues/13421
-    assert not any(t1 == t2)
-    assert not any(t2 == t1)
-    assert all(t1 != t2)
-    assert all(t2 != t1)
+    try:
+        np.result_type(t1.dtype, t2.dtype)
+        np.broadcast_shapes((len(t1),), (len(t2),))
+    except (TypeError, ValueError):
+        # dtypes are not comparable or arrays can't be broadcasted:
+        # a simple bool should be returned
+        assert not t1 == t2
+        assert not t2 == t1
+        assert t1 != t2
+        assert t2 != t1
+    else:
+        # otherwise, the general case is to return a 1D array with dtype=bool
+        assert not any(t1 == t2)
+        assert not any(t2 == t1)
+        assert all(t1 != t2)
+        assert all(t2 != t1)