The road color seems darker and more pronounced. Hence the road shapes are more noticeable and likely also more detailed than before. The width is no longer uniform, but it varies continuously. So the pedestrian streets (bike and walking paths) look more distinct from roads for cars.
I also experience this new coloring scheme on desktop. While it has been rolling out for the app since a few months ago as I mentioned before, for the desktop it has been rolling out since only a few weeks ago.
I prefer this coloring.
About the road width it is another change and not directly related to colors. Indeed it has been available since 2020 and now it seems Google is expanding the street-level details to more cities.
The changes extend to Sat Nav as well where the route you are designing is now in royal blue dots while the Street View lines are still the same blue. This makes it far easier to make a custom Sat Nav based on where the Google Car, Trekker went.
You could check this further by creating navigation to see if the missing road or bike paths pieces are actually missing or only the display is broken. If you do this please share screen shots of the results.