No, I don’t think it’s an effective treatment. Perhaps it could become a useful tool someday with more research and development but even then it could never be more than a minor part of a treatment plan. It can certainly not serve as a substitute for the medications we already know to be safe and effective.
For the most part, those who make claims about neurofeedback for ADHD are motivated by personal bias against medication and lust for conspiracy theories (Drug companies are Evil, don’t’cha know?) and the desire to consider themselves somehow smarter, wiser and more prescient than the professionals.
There’s probably no harm in trying it but don’t let anybody use it to fool you into abandoning an effective prescription and don’t let them infect you with their own prejudices against drugs and those who produce them.