I read that the following language is r.e. but not not-Turing recognizable

*$ L$ : On input $ M$ (where $ M$ is a Turing Machine), $ M$ accepts at least 20 inputs*

I am not sure why it is not not-Turing recognizable., since I could perhaps make the following reduction from $ \overline{A_{TM}}$ to $ L$ given this procedure $ R$ namely:

$ R$ : On input $ <M,w>$ :

- Construct TM $ M_1$ , where on input $ x$ , if $ x=1$ , accept
- If input $ x$ is not equal to $ 1$ , run $ M$ on input $ w$ for $ |x|$ steps. If after $ |x|$ steps, $ M$ does not accept $ w$ , then accept $ x$

From this reduction, if $ M$ does not accept $ w$ , i.e. $ <M,w> \in \overline{A_{TM}}$ , then $ M_1$ accepts any input word, i.e. $ M_1 \in L$ .

Am I missing something here?