I don't remember how it was last year, but after updating to fw 5.90, the colors of the roads in the navigation map are always the same, they do not change according to the chosen theme.
Theme colors change only when previewing and with great zoom-out.
Samples for Suomi:
Samples for United Kingdom:
Road colors by type
Re: Road colors by type
For the example here are screenshots, in both modes (Motorcycle and Car) is the same Theme, with the same colors.
In the Motorcycle mode Garmin ignore my colors and use some own default.
In the Motorcycle mode Garmin ignore my colors and use some own default.