I’ve known two sets of brothers who lost their mothers at more or less the same age as William and Harry (one to bereavement, one to total abandonment- she moved to Aus with a new lover and never came back to the UK).
In both cases the youngest brother has been left in a state of arrested development, especially emotionally. The older brothers also have difficulties that likely relate to motherloss but not to the same extent as the younger ones.
I suspect it’s just a very bad age to lose your mum in psychosocial terms, causing massive disruption to normal emotional development.
The ‘Stiff British Upper Lip’ stuff of our aristocratic class likely meant that this disruption wasn’t adequately recognised, despite the family having the means to pay for professional support (unlike the brothers I know).
I absolutely agree with the above post that Harry has probably been like this all along, but has been ‘scaffolded’ by institutions (boarding school, the army, the firm and their men in grey suits) and Meghan has encouraged him to run away and let it all hang out, not realising that what would hang out is an emotionally stunted, petulant teenage boy who moans about both normal family stuff (the eldest getting a bigger bedroom, his wife having to pay for IKEA because the antiques aren’t to her liking, not wanting to risk a cold sore from a shared lipgloss) and overshares in a spectacularly stupid way.
How on earth he now reconciles his current American social justice persona with publicly boasting about his military record I have no idea.
Surely what’s left of his current sympathetic audience won’t celebrate him killing multiple people, especially as he could easily have avoided this sort of active deployment and spent his military time doing something benign but helpful, like his brother’s search and rescue?