It varies by province and there are definite shortcomings. It is actually pretty shameful that we brag about it. As other users have noted, the wait times are ridiculous, there is also a shortage of GPs in many areas…

• my mother has not seen her GP face-to-face since December 2019; the lady up and took off to another part of Canada! No doctor came to replace her so she handles things remotely.
• my mother once also had a test and the doctors said, “this is probably cancer, you need a biopsy” the next appointment was 9 months later. She managed to get in 6 months later by calling every day. The results came back and it was indeed uterine or ovarian (can’t remember) cancer that had spread and developed into lymphoma. Nthey asked her, “ma’am, why didn’t you come sooner!?” Now, once the diagnosis was made it was a different story. She was treated and had multiple operations and chemo and radiotherapy and is now fine.
• I was misdiagnosed with a disease and found out 16 years later that I absolutely didn’t have that disease (luckily there was no treatment, just minor lifestyle changes)
• getting into a walk-in clinic can be literal hell and if you don’t have a car you are just plain screwed.

Those are just anecdotes from Nova Scotia, though.

Is it bad enough to go to the US? If you have some money and don’t want to wait, that is what lots of people do. Just get it taken care of, nip it in the bud instead of waiting and worrying.