The GHIB multi-use path was announced way back in 2017 when the bridge was still being designed, so I'm not sure why this is being treated as news.
Regardless, it will be interesting. Both corresponding sections of Detroit and Windsor are terrible places to cycle, though. The Windsor side near the bridge is almost entirely industrial land with highways (I used to live near there), and the Detroit side is the same but with the addition of abandoned properties.There is hope that the bridge will revitalize the area on the Detroit side but I'm pretty sure Detroit wants to make it an industrial-only area.
The Herb Gray Parkway on the Windsor side has a very long cycling trail that could eventually be connected to the bridge, but it stops at Malden Road, pretty far away from the GHIB site. I'm not sure if they plan on building more trail to connect it to the bridge, but I hope this is the case. Ideally, a trail alongside Ojibway Parkway that runs from Sandwich Town to Ojibway Park should be built as well, but we will see if cycling/hiking-friendly investments are made in the area to connect everything together.