The Chinese population in Vancouver has evolved with different waves of immigration of the years. There's still a lot of Cantonese spoken due to the waves of immigration from HKG but you're hearing a lot of Mandarin nowadays due to the immigration from mainland China.

Chinatown isn't the central hub that it used to be as Chinese markets/stores (T&T, Chong Lee, etc) have sprouted up throughout the lower mainland so the need to head to Chinatown to shop for Chinese groceries has diminished. While Chinatown is still a functional Chinese marketplace it's a bit of a shadow of its past with a bunch of trendy/hipster type restaurants and condos sprouting up around its fringe.

The largest Chinese community nowadays is likely in the suburb of Richmond with a few high concentration areas of Chinese businesses and restaurants (eg Aberdeen Mall vicinity/along #3 Road). In fact, local news publicized that the city is looking to hire a signage coordinator to encourage businesses to include English in their signs. Richmond isn't really a pedestrian friendly so it's a different experience from Chinatown. The closest experience IMO would be visiting Aberdeen Mall and larger shopping centres like Yaohan Centre (or even just the "regular" malls like Landsdowne or Richmond Centre).

Also, as mentioned, Chinese markets/restaurants are fairly distributed with pockets in East Vancouver along Victoria Drive, Fraser, Kingsway, etc.