As much as Smith is washed, and unlikely to rebound, this is probably a better option than giving big money and term to a middling option like Petr Mrazek, Semyon Varlamov, etc. I guess we don't know the term or AAV for Smith, so this could be bad, but I'd expect this to be a small AAV with some bonuses of variable achievability on a one-year term. Goalie will remain a weakness and question mark for the Oilers but at least their tandem shouldn't cost more than $7M for this season, and hopefully less than $6M. That would give them some more room to spend on their other openings.
The Oilers still need to fill two winger slots and a third-line center spot. After the Sekera buyout they had ~$10M to spend on those three spots plus their backup G. If Smith comes in at less than $2M AAV, the Oilers can maybe get a real name in UFA. Still, I'd expect that "name" signing to wind up being a regrettable contract. And it appears they are rumoured to be in on Corey Perry so that would likely fit the bill of big name, washed up, regrettable and overpaid. I'd actually love to see Perry sign a reasonable deal. Just don't think it'll happen.
Should also mention that Smith had his best years under Tippett in Arizona. That was many years and many injuries ago, but likely a reason Smith signed on. Worth asking, are either Smith or Tippett still good?