In order for Openstreetmap to do that, it would have to either:

• Crowdsource the data from people running an Openstreetmap mobile app with location data collection, which doesn't exist and wouldn't be accepted by the sorts of privacy-conscious people who prefer Openstreetmap, or
• Buy traffic data from a company like INRIX that actually goes to the expense of building and maintaining sensors along roadways, which it can't afford because it doesn't get that sweet exploitative advertising or surveillance capitalism revenue.

I suppose it's possible that apps like OsmAnd could provide a feature for users to log into and receive traffic data from their own INRIX subscription that they bought themselves directly, but that would be such a niche feature it probably wouldn't be worth the development effort.

Magic earth is pretty nice but not enough people using it to make it useful like waze

I dunno, it navigates pretty well but I find myself having to use Google for search

it would be nice if it had anything for public transit (I'm my area)

I am not saying traffic feature is bad. I am criticizing the little control we have to not contribute to the statistics. Google is a monopoly and decisions are made by them with little control over our devices.

Traffic feature is cool and for it I would contribute, but just pointing out that google hasn't done it in the best possible way to gather statistics. I wouldn't use traffic feature from google for this one reason.