Do you realize that 67% does not refer to the tax rate, but rather the amount of capital gains that are taxed as income? Meaning that the remaining 33% are always completely tax free?

Example: you sell an investment property for $2,000,000 which you had previously bought for $1,000,000. Your annual salary is $75,000.

In this example, of the $1,000,000 capital gain, 50% of the first $250,000 ($125k) is taxable and 67% of the remaining $750,000 ($500k) is taxable. So, add $625k to your salaried income of $75k and your total taxable income is $700,000.

The total income tax you would pay after the proposed increase (assuming you live in Ontario) is $342,103, which is $320,405 more than you would have normally paid on your salary of $75,000. Therefore, your effective tax rate on the $1M capital gain is roughly 32%, not the 60% you mentioned in your comment.