It doesn't apply just to streaming, any music play does it, it's been that way since at least 2015 on the Rav4, falls in line with Toyota's system policy to eliminate distraction like not being able to enter addresses manually into Nav while moving, mine shows album art when in drive but not moving like setting at a red light with the brake applied, as soon as I release the brake pedal it reverts to the icon, previous gens always reverted to the icon when out of park.
I had the 2016 XLE Rav4 and I was able to see my album covers and the pics of my contacts. Just got the 2019 XLE Premium and it goes blank and I do not like that. Why didn't they just leave that feature? I
My '16 Ltd HV BT connected phone music displayed album art while moving sometimes, my '19 Audio Plus displays when in drive, but only when sitting still, disappears when I start moving, stopped at a red light it reappears.