Are there known benefits to taking low dose naltrexone?

Likely. As you are aware, the internet is full of "anecdotal evidence" about benefits of low doses naltrexone. It is sounds logical that low doses can make your Dopamine receptors more sensitive to your own dopamine.
No. Low dose Naltrexone (ldn) describes the "off-label" use of the medication naltrexone, typically prescribed for opioid dependence or alcohol dependence, at low doses and for other diseases such as as multiple sclerosis. Although there have been dramatic claims about its efficacy in treating a wide range of diseases, these claims are not generally supported by scientific evidence.