Very doubtful. Where are the crises in legal states/countries?
There also wouldn't be a statistic if people do not report to a doctor about 'hearing voices' for example.
Also the Netherlands has shown the increase in schizophrenia
https://www.who.int/substance_abuse/publications/cannabis_re...
For a deeper discussion see
https://theconversation.com/if-cannabis-is-getting-stronger-...
Also the low rates of smoking in NL undermines you because it directly demonstrates that legalisation doesnt lead to high uptake.
No crisis in California, Washington or Colorado. We are all doing just fine.