Even with what you’ve described, smart can still apply. The goal that’s set would be a specific, desired outcome, the who, what, where, when, and why of how you get there, is up to the best judgement of the team. It’s measurable in the way of having some way to determine that the specific goal was achieved.
That’s S and M, for A, achievable, I’m sure the team would let you know if a goal is not able to be reached. If they didn’t think it can be done, they would not waste time trying.
Relevant is mostly irrelevant for the workers, that’s more whether management decides it is relevant to the companies goals.
Time-based … This is the part I’d have the most trouble with. It takes however long it takes. As long as nobody is dragging their ass, it shouldn’t take any longer than it needs to, and putting a time constraint on it just puts undue pressure on the team for no good reason. As long as progress is steady and things are getting done, then time shouldn’t really matter all that much.