Generating an evil wallet where the last six characters or so match the original is probably feasible. I heard of this being done to SSH host keys. Someone invented randomart images to make it easier for humans to compare binary strings [1], but I'm not sure how well they fare against similar attacks.

[1] https://bytes.zone/posts/what-is-the-randomart-image-for/

I have been targeted by scammers who generated wallet addresses with 15 of the same characters.

I am sure it is, but oh well. You always have to be careful about money.