Exactly this. Not only is the S less powerful, it doesn't have a disc drive. Long-term, the X will run games better, for longer. It will also hold its resale value better, since even 5 years down the line, when the S becomes a brick after the system online store shuts down and you can't purchase or download Digital games (Sony anyone?), you'll still be able to load discs into the X, either natively or via some workaround someone will likely come up with.
Sony just announced, for example, that the store for PS3, PSVita, and PSP will be closing down later this year, just 4 years after they stopped manufacturing new PS3s in 2017, and just two years after the last brand new PSVita rolled off the assembly line in 2019. In theory, you can still redownload your old games after the store shuts, but who knows how long that will last. Hopefully by then all relevant systems will be hacked so we can still download old games from third-party sources.
All-digital consoles, reliant for basic functionality on some else's data storage servers, just seem like a terrible idea. Maybe I'm just getting old. Nevertheless, judging by the resale value of old NES, SNES, Genesis, N64, etc. consoles, being able to play with your children or grandchildren on X discs may one day be a real thing, while the S will likely require much more effort to continue functioning.
