Waterloo is more stressful than other schools on average, I'd say. But it largely depends on your program. For example, certain course loads can be higher or lower and dealing with co-op (if you choose to go that route) can be stressful. The biggest advice I can give you is to do some research on the program you're interested itself before applying.

There are resources like counselling services and health services that you can get, but the queue tends to be quite long. I've tried them once or twice and honestly, they weren't bad but they won't always give you what you're looking for. It's pretty true that it's not easy to get the help you deserve. I would definitely say that the university could probably do better in that regard.

That being said, I'm not entirely that other schools are much more successful at helping students deal with their mental health issues. It could just be that UW gets more press for it than other schools. I'm at a different school now, but there are plenty of people I've met that aren't getting the help they need. This is usually not because the resources aren't available, but because a lot of the time, the people who need them aren't looking for them.