The Series X will be a much better purchase long term since in a few years games could be running poorly on the S. I'd only recommend the S if someone really can't afford the X or for getting a second Xbox for whatever reason.
Whether or not Series S games will run poorly is uncertain, but there is certainly more potential for Series X games run better.
But like the OP said, if you just want access to the games and the highest fidelity isn't important, then a Series S should be fine. For $200, that's something people will consider.
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