If the phenomena is real then it means that some theory is wrong or incomplete, but not necessarily conservation of momentum. In the paper they give some ideas

If the phenomena is real then it means that some theory is wrong or incomplete, but not necessarily conservation of momentum. In the paper they give some ideas how conservation of momentum can be preserved. More research needs to be done for sure, but the phenomena being real does not necessarily mean a rewrite of physics. We have to wait and see if it is real and what the underlying physics is. Only then we will know how wrong/right our theories are.