Where I live having been non-voluntarily committed to mental care facility makes you ineligible for concealed carry permits and firearm ownership. There is an appeal process I believe once you are no longer considered mentally disturbed. Personally I think this makes sense. If you are deemed a danger to yourself or others by trained medical professional(s) I don't think you should be allowed to own a gun, whether you be a veteran or not; until you receive adequate treatment to be "in your right mind" again. I think this particular attempt would be redundant though as I would think that most states already have laws regarding mentally unstable people and gun ownership.
I do think that the government is trying to move towards a more arbitrary definition of who is and is not prohibited based on mental illness. Giving much greater discretion in creating prohibited persons. It is in fact the perfect loophole for moving it further from a 'right' and insuring it is a 'privilege' only those deemed worthy have. Now there is certainly mentally unhealthy people I do not want to have a firearm, but mental illness diagnosis is largely discretionary.
Virtually everyone in society has symptoms of mental illness, because mental illness describes anything which is abnormal as unhealthy, and nobody is actually 'normal'. So everyone has some abnormal elements to thier personality. (In fact being perfectly "normal" would be abnormal, as there is no normal.) Which means it is discretionary whether those symptoms are considered a mental illness or not. If the person is having problems, it can be considered mental illness requiring treatment. If they are not it can be considered normal.
If you want to give them happy pills or something to "help", they can be diagnosed simply to create a medical condition that needs treatment and thus allows prescriptions.
It is entirely discretionary. Someone stating "molon labe" or associated views could for example be described as having symptom of mental illness.
What is considered "abnormal" enough to be a serious enough symptom for diagnosis of various mental illness can also vary based on the beliefs of the individual performing the diagnosis. Which can very regionally based even on politics and views of the psychiatrist.
For example in New York City or San Francisco, someone heavily into firearms, hence weapons, may be abnormal. Combined with some other minor "abnormality" or "symptom" it may very well be enough for a psychiatrist to feel they are suffering from ____.
Now combine this with politics in a location unfavorable to firearm rights, knowing full well that those involuntarily committed can be denied firearm rights.
Anyone who shows up in Judge Brady's court, especially someone into firearms, can be ordered to undergo a psychiatric evaluation. By a psychiatrist who is known to be inclined to find illness who does such things routinely for the city. Thus anyone appearing before the court could arbitrarily be denied the RKBA at the court's discretion.
Don't want someone with a gun? Send them to psychiatrist Brady.
Further while your state can allow petitions, it is also a federal prohibition. So even if your state says you are no longer prohibited, under Federal law you still are.
If they can expand the number of discretionary diagnosis which prohibit the RKBA, and create federal level databases that track all these records ( previously considered private medical records) then who can retain the RKBA is entirely discretionary.
Certainly visiting or receiving any psychiatric help is already shaky ground, and may allow someone to prohibit you in the future.
For example if a soldier has a history of being treated. If one day they have a bad time, maybe get a divorce, lose thier job, lose a loved one etc resulting in emotional problems.
Thier mental health record can be combined with thier current problem and is much more likely to result in involuntary action being taken to 'protect' them and others. Making them a prohibited person for life. Without that mental health record, they are much more likely to just be viewed as someone going through a rough time, and unlikely to receive involuntary treatment.
So the more someone is in the "system" and has a "record" (mental health) the more likely thier rights will be at the discretion of others in the future.
Every single person in the population can be diagnosed with mental illness by someone who has received an education in psychiatry. Everyone displays the symptoms of multiple mental illnesses. It is just up to discretion whether those symptoms qualify as mental illness or not.
This is not to belittle psychiatrists. They provide a useful element in helping some in society, but I do not think people realize just how much discretion is involved. It is not like a medical physician saying someone has a real disease. It is instead someone saying that someone's views, or thoughts, or responses are abnormal enough to be a disease. But what is abnormal is highly discretionary.
As for the particular legislation. What was passed was primarily the tracking portion, it did not expand prohibiting diagnosis. Previously confidential medical records are now being reviewed and a massive database being constructed and maintained. A couple states have made such creation much easier, and hence the federal database is primarily composed of those states at this time. However once they computerize all medical records across the nation, as is happening, it will be much more widespread.