Hulu hangs on startup every time. Spin spin spin. The only workaround is to restart our appletv 4k every time.
Hulu seems to be a memory hog. If you do the double tap on the home button and then swipe up to close apps you will free up memory for the Hulu app. Too bad there isn't a design standard that requires apps to play nice together or close after a period of nonuse.
Try deleting the app and reinstalling
Same experience I’m having. Apple and Hulu need to prioritize getting this fixed. I cut cable for the first time Ever to move to Hulu tv. Having to reboot each use use is inexcusable and not even a short term workaround for non-techies in the family.
You can force quit the Hulu App, then launch again
you might also try troubleshooting your network
Force the highlighted app to quit
On the Siri Remote, press the Home button 
twice quickly.
Windows representing each of the open apps appear in a row on the screen.
Switch quickly between Apple TV apps - Apple Support
Our network is quite fast, but force quit does show several apps open. Perhaps its a memory problem and the Hulu app is requiring more than the available memory.
Hulu App Hang
