Possible resolution:

Change in 7.5.6.3 [expr.prim.lambda.capture] paragraph 6 as follows:

  auto z = [a = 42](int a) { return 1; };   // error: parameter and conceptual local variable have the same name

[Accepted as a DR at the November, 2022 meeting.]

The comment in the example in 7.5.6.3 [expr.prim.lambda.capture] paragraph 6 refers to "local variable", but should refer to init-capture instead.