Yes, I think so.

I also think it goes further.

For those seeking the truth, the Sabbath is a good indicator for identifying God's will and therefore God's true people. Being part of God's people is not a guarantee of salvation. However, knowing and doing God's will: yes!
There is real confusion (contradictory teachings) within Christianity, and this is truly draining, exhausting, even discouraging for those who sincerely seek the truth. But there are simple and effective indicators that make a difference in this confusion, such as the Sabbath.