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That the source is a dated

It's from 2007 - "dated" only if there's reason to suppose that more recent evidence weighs against the conclusion that alcohol use may trigger psychosis in people who are vulnerable to developing schizophrenia. Can you offer any reason to so suppose?

Australian Department of Health web page

That was clear from the URL so not omitted.

that does not advocate your position.

I don't know what this claim of yours has to do with allegedly omitted context. Are you saying something else from that source says alcohol is not harmful to mental health?

comorbidity

is not mentioned on the page in question.

alcohol is more addictive than marijuana, more violence-increasing, and the only one of the two that can lead to fatal overdose.

I notice you've declined several opportunities to address these points. Why is that?

My research in PubMed uncovered a study in Finland reported in 2013 that found that for patients hospitalized with substance-induced psychosis, over the next eight years, 46 per cent of those whose psychosis was induced by cannabis became schizophrenic, while such a conversion occurred in only 5 per cent of those whose psychosis was induced by alcohol and 30 per cent of those whose psychosis was induced by amphetamines.

Or, in plain terms, almost half of those who were hospitalized for cannabis induced psychosis became schizophrenic, which was worse than the rate for amphetamine psychosis. Alcohol psychosis converted to schizophrenia only 5 per cent of the time.

J Clin Psychiatry. 2013 Jan;74(1):e94-9. doi: 10.4088/JCP.12m07822.

Substance-induced psychoses converting into schizophrenia: a register-based study of 18,478 Finnish inpatient cases.

AUTHORS: Niemi-Pynttäri JA1, Sund R, Putkonen H, Vorma H, Wahlbeck K, Pirkola SP.

BACKGROUND: Despite the clinical importance of substance-induced psychosis (SIP), few studies have examined the course of this condition after its acute manifestation.

OBJECTIVE: To investigate the rate of SIP conversion to a schizophrenia spectrum disorder and the length of follow-up needed to catch the majority of these patients whose diagnoses change. In addition to the conversion rate and pattern, we wanted to look for possible related factors.

METHOD: Using the nationwide Finnish Hospital Discharge Register, we followed all patients (N = 18,478) since their first inpatient hospital admission with a diagnosis of SIP (codes 2921 and 2928 in DSM-III-R and codes F10-F19 in ICD-10 with a third digit of 4, 5, or 7) between January 1987 and December 2003 in Finland. Patients (mean age = 43.7 years, standard deviation = 13.5 years) were followed until first occurrence of schizophrenia spectrum disorder, death, or the end of December 2003, whichever took place first. Conversions of discharge diagnoses into schizophrenia spectrum disorders (codes 2951-2959 and 2971 in DSM-III-R and codes F20, F22, and F23 in ICD-10) were recorded at follow-up.

RESULTS: Eight-year cumulative risk to receive a schizophrenia spectrum diagnosis was 46% (95% CI, 35%-57%) for persons with a diagnosis of cannabis-induced psychosis and 30% (95% CI, 14%-46%) for those with an amphetamine-induced psychosis. Although alcohol-induced psychosis was the most common type of SIP, 8-year cumulative risk for subsequent schizophrenia spectrum diagnosis was only 5.0% (95% CI, 4.6%-5.5%). No differences were detected with regard to gender, except for amphetamine-induced psychosis, which converted into a schizophrenia spectrum disorder significantly more often in men (P = .04). The majority of conversions to a schizophrenia spectrum diagnosis occurred during the first 3 years following the index treatment period, especially for cannabis-induced psychosis.

CONCLUSION: Substance-induced psychotic disorders predict schizophrenia spectrum disorders to a greater extent than previously thought. The intensity of clinical attention focused on substance-induced psychotic disorders should be increased.