We stopped our xfinity tv service a few months ago and kept the internet service. Really happy to have lost the bill and the drone of nonsense (cable news, etc) that comes with it. We also listen to xm or other music most of the time.
Roku itself is free (other than purchase price or their own subscription service). It’s just a device to access services. One thing I really like is that subscription services are monthly. You can add and drop as you like, rather than automatically paying the monthly cable fee. When the second part of Dune comes out on HBO, for example, I’ll grab it for a month or two, watch everything I want to watch, and then cancel.
Accessing live sports on the networks is something that adds cost. We wanted to watch the World Cup and needed to subscribe to Hulu for a month or two at 80$+. I miss watching lots of sports, but the cost is silly and can’t really be justified, for me anyway. I sub to Netflix, Amazon, Espn+ and peacock. Apple TV off and on. Watch a ton of YouTube stuff also, all through the Roku.
If you want to watch stuff like you mentioned, American idol, etc, you can get a much less expensive subscription to hulu (under 15$ I think) that lets you watch just about anything on replay. You just can’t watch it live for the less expensive service. Next day, I believe, and usually all episodes of a given season, if not all season.
Long ramble. We’re saving money and using time more pleasantly after canceling our cable equivalent.