If anyone gives him a diagnosis based on these things without evaluation, run from that person. No professional mental health expert should diagnose someone they haven't met. As for the things you list, that does not confirm mental illness (which is why no one should diagnose without evaluating for themselves). As I said previously, a number of medical conditions can and do present with the same exact symptoms noted above. In order to diagnose mental illness, all other causes must be ruled out and given that we know next to nothing about his medical status, we can't do that. Drug intoxication with certain drugs, such as cocaine, PCP, and LSD, can also lead to delusions, paranoia, and hallucinations. These drugs can also make someone very violent and combative. Likewise, withdrawal from certain drugs, including alcohol, can also lead to delusions, paranoia, and hallucinations. Longterm drug use can also damage the brain to the point that you experience psychotic symptoms as can dementia, AIDS, syphilis, some autoimmune conditions, some legit medications, and a number of other diseases.
What really argues against mental illness in his case is the fact that he is able to record videos, edit (?), and post to YT. YT isn't as easy a platform as say Twitter or Instagram. Most people who have true schizophrenia or psychotic illness don't have the organizational skills and executive function to be able to do that.