The fact that H+M started to do royal duties and engagements and became full time royals and that Meghan said she wanted to hit the ground running, suggests that Harry both wanted to be a full time royal, and that he explained to Meghan what was going to happen. It is perfectly possible that despite this, that Meghan did not truly understand what this meant, as she is a citizen of a country that doesn’t have royalty.
I do not know what was in Meghan’s mind, or whether, as has been speculated, that she never intended to stay the course, but she didn’t really give it a fair go did she? And why has Harry done a 360 degree turn, and gone from working alongside his wife as a full time royal, to total rejection of his/their expected role? It’s all very strange. As far as I am aware, Harry didn’t appear to want to reject his role previous to Meghan, and he was involved in various mental health and armed forces charities, and he appeared enthusiastic about this work, prior to Meghan.