Harry is also been known to do the Royal Wave, there are photos of him doing so, but out of respect for his privacy from photo ops, I won't post any of him here.
It's not unknown tho for royals to unRoyal themselves, King Edward famously abdicated himself after only a 10 months of being King to marry his divorcee American wife Mrs Wallis Simpson, who after this most notorius departure was known as the Most Hated Woman in the UK.
They weren't allowed to settle in the US though and had to exile themselves to the Ritz Hotel in Paris. France. No children, only dogs...pugs not corgies or dorgies.
Then his little brother 'Bertie' aka George became King instead. The spare.
This official letter..which he himself wrote and signed meant he could no longer work as a King or represent the country.
Harry didn't write or sign and official letter signing away his Royal status or title. I guess the memoir and his Oprah interview were enough to indicate he wanted to leave his role behind. The thing is Edward and Wallis were totally ostracised by the spare Royal family for his decision, were not invited to any garden parties, couldn't go to the races at Ascot, or own any land in the UK. Wallis or as she was known as the Duchess, didn't care about these things so much, from reading HER memoir it was all about housekeeping/decorating a palace. She wanted all the creature comforts but not the responsiblilty or duty of being Queen.
It was probably too much to expect of anyone anyway. Not everyone wants the job.