In my experience, haters are some of the most passionate users, if you can do even the smallest thing to demonstrate a desire to improve, they'll often be huge advocates over the medium term.
I was working at a startup and we got some frustrating and hostile feedback from a user, I responded by acknowledging the issue and sending them a beta build that attempted to fix their issue. (it did not, but...)
Just reaching out and trying to engage made an enormous difference. They ended up contributing significantly to isolating and fixing that specific bug and others in the future, and referring us a few customers to boot, if I remember correctly.
I was working at a startup and we got some frustrating and hostile feedback from a user, I responded by acknowledging the issue and sending them a beta build that attempted to fix their issue. (it did not, but...)
Just reaching out and trying to engage made an enormous difference. They ended up contributing significantly to isolating and fixing that specific bug and others in the future, and referring us a few customers to boot, if I remember correctly.