The only key points that haven't really been made here, so far:
The topology in the Meraki Dashboard is dynamically created and (with a bit of time lag) self-updating; if someone changes something in the topology, the topology gets updated, with no input required from the admin - provided the devices remain connected, of course.
While you can download the created topologies as .svg files, I'd be surprised if anyone uses that feature very much; why create static content, when you can just look in the Dashboard for what's actually there?
Hence I don't think the Topology tool and Lucid Chart (or Visio, for that matter) are greatly comparable. You couldn't use the Meraki Dashboard to create a design schematic, for example.