Another question for people who understand these things better than me, if Ontario has one of the highest deficits and highest upper income tax rates in the OECD, but doesn't have the corresponding social program spending to go along with it, then where is all the money going to?
I can't speak to Ontario, but usually the answer in other jurisdictions is: nice fiscal arrangements for middle-earners. Low middle-income tax rates, free childcare and low property taxes, for instance. Maybe low sales tax, but in practice lots of jurisdictions make this effectively progressive using exclusions.
Another answer could be: weak demographics, low participation rates, meaning fewer workers and more tax per worker, to pay for more dependents.
The final possibility, rarer nowadays: like the famous top marginal rates in the 1950s USA or 1960s UK, almost nobody is actually in the tax bracket. This doesn't seem to apply to Ontario