That looks like a TCL Roku TV model number. I have an older version (32S302) in a guest room, and it's running Roku OS 10.0.0 build 4209-08, same as yours.
It's running YouTube 2.20 build 93005146, same as yours.
It crashes back to home page after launch.
Removing, rebooting, and reinstalling does not help, as others have reported. I'm confirming this for YT 2.20
That seems to confirm that YouTube hasn't made version 2.21 available to certain Roku devices yet, and the ones people are reporting are TCL Roku TVs. I'm not yet comfortable saying it's all TCL Roku TVs, but it is definitely some TCL Roku TVs. It could be other brands as well.
Google determines what versions of their apps work on what Roku devices. In fact, all app developers do. It appears that Google has not yet rolled out 2.21 to all devices, and the devices we've found are all TCL Roku TVs running 10.0.0 b93005146. YouTube app 2.21 works on my devices that have that update.
Perhaps @RokuDanny-R or @RokuKariza-D can offer some input. For now, it looks like those with the issue are awaiting an update from Google on the YouTube app.
Roku Community Streaming Expert
Note: I am not a Roku employee.
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