Kudos to them for landing a nature publication but I really would temper this level of excitement (??a top link on HN??) at a basic science research publication discussed in a press release from a university highlighting it's researchers.
My read is it is down to decreased CXCL13 expression and type I interferon expression in blood of a small number of patients, controls, and cell culture which gives direction for further study. CXCL13 was published as a possible RA biomarker half a decade ago and crickets since then clinically. Is it causal or a consequence of chronic inflammation? Type I interferon signature has been looked at heavily for over a decade and is clearly relevant in SLE but still only just over about half of lupus patients have it and the signature is by definition broad expression of hundreds of genes that affect innate and adaptive immune system components.
We DO need better treatments for lupus patients but it's a very variable disease in severity, clinically, and in terms of biomarkers making it difficult. I mean the best drug that everyone with lupus should be on barring a good reason is an old antimalarial (that doesn't treat COVID) and then we add to it. If you are interested in other new-ish therapies for lupus take a look at anifrolumab, belimumab, voclosporin, and even newer CAR T stuff. Important to consider the manifestations being treated with those in the studies e.g. belimumab with skin, joint, kidney but nothing for hematologic/cardiac/neurologic manifestations.