I haven't seen it yet but my thoughts on what I've picked up so far...
I think it's a shame if they were really complaining about Nottingham Cottage, it looks like a lovely and characterful home and as others have pointed out, Kate and William lived there for a while. If they felt it was a slight on them, that was silly IMO and definitely the kind of thought you keep to yourself.
Re William and the shouting, I can believe that. Purely anecdotal but I believe he's always had a temper and could be very nasty if it came to it. OTOH arguments happen in families, emotions were running high and I'm sure Harry was angry as well. But I believe him when he says he was terrified, he was probably an anxious wreck anyway throughout that period and would have obviously felt very attacked. Putting that into context that it does sound as if KP were the source of many of the negative stories about H&M, I think Harry is deeply angry and hurt and burning his bridges with William now. It's very sad but honestly not that surprising. I'm not sure they've handled things terribly well, but if my brother was using the press to plant negative stories about my spouse, I wouldn't be particularly forgiving either. Caveat: obviously we don't know William's side of things. But it sounds like it was pretty ruthless and the relationship between the brothers is now dead and buried, sadly.
WRT their comments about jealousy over someone coming in and doing the job better, I think that's actually true but may have been better left unsaid as well. But this is them having their say and I think they felt justifiably that they were working hard and bringing a lot of good publicity to the Royals while being treated pretty shabbily by way of the press.
I'll comment more when I've actually watched it. 😊