Roku voice remotes can only control the power and volume of TVs. That may be enough if you only watch streaming content, but you'd have to be able to set the TV to power on to the Roku's input. Most TVs power on to the last input used, so you may only have to select the input once. I believe only the least expensive Roku device still doesn't include a voice remote. There's plenty of cheap universal remotes you could get for your TV.
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