Nothing is really that far away in regards to attractions in the city centre, from either hotel. Waterfront may be a few steps closer to Gastown or Stanley Park but is a few steps farther from Granville Island or Robson street. So my comment re being more central may be a bit misleading. Really to me, it is about the difference in the hotels themselves in terms of ambience etc.
Regarding attractions, one of our favourite things to do in Vancouver is visiting Granville Island. A few blocks walk from the Hotel Vancouver you get to a ferry dock where you catch one of the little ferries across.
https://vancouversbestplaces.com/top...r-ferry-boats/
https://theaquabus.com/
» Dock Locations
The two ferry companies can get you to various attractions in a more interesting way than public transport or taxis.