It looks like CyclOSM and Open Cycle Map render that proposed section well enough. Though, without looking closely at the map key, folks may think that trail really exists. Personally, I am in the "only map reality" camp. Maybe, the suggestion on the "proposed" key's wiki page to use "proposed: route=bicycle" would work better, as "this makes it clearer to database users that this route is not yet in existence."
https://wiki.openstreetmap.org/wiki/Key:proposed
That page also states, "
You are also encouraged to add the source for the plan with source=*. Please take care about copyright issues and don't copy from plans you're not entitled to do so.

Objects without clear evidence that there is some real active plan to construct it should be removed from data.
"

And, I doubt that is a true "cycleway". The only cycleway I know of in Michigan is a half mile long section on MSU's campus. Have a look at multi-use paths on the Michigan Wiki.
https://wiki.openstreetmap.org/wiki/Michigan#Pedestrian_ways
In fact, many of our paths are signed for wheeled users to yield to foot traffic. Which would more accurately be highway=footway + bicycle=yes + segregated=no or highway=path + foot=designated + bicycle=yes + segregated=no
However, ignoring those signs, most have been mapped as highway=path + foot=designated + bicycle=designated + segregated=no