Ellen White did far more than suggest that keeping a Saturday Sabbath and worshiping on Saturday was a nice gesture or a way of remembering Old Testament times. Take a look at these two quotes from her writing.
Incidentally, EW refers to the Sabbath commandment as “the fourth commandment,” which it is in Protestant Bibles. Roman Catholic Bibles number the commandments differently, so it isn't the fourth commandment for them. EW is unaware of this.
<< When the foundations of the earth were laid, then was also laid the foundation of the Sabbath. I was shown that if the true Sabbath had been kept, there would never have been an infidel or an atheist. The observance of the Sabbath would have preserved the world from idolatry. The fourth commandment has been trampled upon, therefore we are called upon to repair the breach in the law and plead for the desecrated Sabbath. The man of sin, who exalted himself above God, and thought to change times and laws, brought about the change of the Sabbath from the seventh to the first day of the week. In doing this he made a breach in the law of God. Just prior to the great day of God, a message is sent forth to warn the people to come back to their allegiance to the law of God, which antichrist has broken down. >>
Chapter 12, 2nd page
Ellen G. White (2010-12-05). Life Sketches of Ellen G. White (Kindle Locations 1109-1114). Copyright © 2010, Ellen G. White Estate, Inc.. Kindle Edition.
<< I saw that God had not changed the Sabbath, for He never changes. But the pope had changed it from the seventh to the first day of the week; for he was to change times and laws. >>
Last page of same chapter.
These are very extreme statements, not justified by anything in the Bible.