I'm not convinced it is actually a life of luxury. Financial security, sure - but she no longer has the luxury of being anonymous, free and able to make spontaneous choices. Everything she does now will be under the microscope, from the first inkling of a pregnancy to her fashion choices. It will be like being dissected every day, and that will take some getting used to. She wil also have constant security wherever she goes which may be novel at first, but could become wearing.
She has also become a Forces wife which has it's own set of challenges with regards to jobs, sudden moves, separation and the job always, always coming before anything else. Add to that being married to the heir to the heir and she is already third in the pecking order after service commitment and then royal commitment.
Given the massive sulks that the PoW threw when Diana garnered more column inches than he did, they will have to avoid 'upstaging' the PoW again, and are presumably treading carefully until she finds her feet. I would imagine that it is alarming and tiring going to an event where loads of people turn out to see you; you have to master what the visit is in aid of and ask intelligent questions and look fascinated by all that you see. It is a big ask.
We don't expect people to perform perfectly in a new job - we train them, mentor them and support them. That could be what is happening here; she will have a period of 'training' on protocol and what to expect and will try it out in Canada, at the Trooping of the Colour and the celebrations for the DofE's 90th. Once she is up to speed she will take on more, but they have obviously learned lessons from both Diana and Fergie and are breaking this one in gently.
Seems mean to begrudge them some time together, after all, once the circus starts in earnest, they won't have much of it.