I would tend to agree.
As a first and upfront caveat, Canada has a smarter system of taxing capital gains than the U.S. does. We have a fairly clean and simple model, relative to the complex multi-rate U.S. system that has a number of classes, a number of holding periods. So I like the Canadian system as a model, but I would certainly agree that the rate is too high, especially given that there remain, for instance, accumulated inflationary gains present in taxable gains. So that's something to take note of.
You can't, or rather I wouldn't, recommend, however, simply lowering the capital gains tax rate without paying attention to what's going on with the different taxes and small business taxes.