you’re not going to be able to eliminate these completely because like you said in the comments, they’re likely searching using the same terms as your target audience, so adding negatives would also prevent your target audience from reaching you.
best option you have really is to do a better job qualifying via your lead gen form and tracking marketing qualified leads as your primary conversion. maybe stop driving phone call leads if phone call leads tend to be low intent.
this way at least google ads bidding algo isn’t being trained to bring you more of these type of low quality leads.