Don't deny our history - just let us learn to grow from it
Sir John was a major contributor to founding our nation - 150 years ago! Canada, and some of the world, has evolved since then. Many people then considered as caring and responsible shared many of his views. True, he was far from perfect even by the standards of his time - reprobate, drunkard, 4-letter word expert, just to name a few.
But, look at other nations! We in Canada have had more constructive and more representative federal governance than most other nations on our planet. We owe a good part of that to our first prime minister, not just in spite of his human flaws, but perhaps even because of them.
In my home town of Shipman's Corners (now part of RM Niagara) there is a statue of a man who committed outright fraud by modifying the survey data for his proposed canal to irrigate his lands to reduce its projected cost by 50%, then later mulcted the indigenous peoples of the Grand River (read Caledon) of a huge portion of their lands and entitlements. It's on a lot higher pedestal than the Victoria Sir John too. Merritt's contributions to today's Canada were tiny compared to Sir John's, and despite all the historical research since then, Sir John was almost an angel of probity compared to Sir William Hamilton Merritt.
If you are going to apply today's standards of belief to Sir John, there are a lot of statues that would come off second best before his.
Keep the statues - they are part of our real history. Just add a plaque below them to explain how our views have changed since they lived. And, make those plaques replaceable! A few generations from now, we'll undoubtably have different views on our predecessors.