"Look what goes around comes around, if in 2008, the world was like we want to embrace China, in 2016 we want to jettison China, mark my words mainstream thinking will come back to wanting to embrace China again, it will because the economic opportunities are vast," Sir John said.

There's actually a really clear, direct reason that Obama's shift to the Pacific and then Trump's policy changes happened (IMO I still think Trump was actually a patsy to flip the Washington consensus against China).

Prior to Xi, the theory was that China would eventually liberalize and become part of the global rules based system, and that they were not a revanchist or expansionist state, other than the Taiwan question. In addition, it was viewed that the struggle was not ideological and that China's economic success being a result of essentially a form of capitalism would lead to them not attempting to offer an alternative to the west in the ideological / political sphere.

Xi undid that theory by explicitly stating and acting is if China was in fact revanchist (although not yet expansionist) , explicitly stating and starting to push an alternative ideological / political vision, and explicitly stating / acting to offer an alternative to the west in the ideological / political and other spheres, and becoming significantly more aggressively diplomatically and in terms of intelligence efforts. Combined with the largest naval buildup in the history of the world, it's no surprise that the west decided to flip the narrative and start pressuring them.

Tying that back to NZ, Chinese efforts to help countries like the UK, Canada, and New Zealand counterbalance American interest became significantly more assertive and aggressive with Xi's rise in a way that they could not ignore.

tl;dr: Basically, Xi slapped his cock on the table and announced China was taking over, which was much to un-subtle to avoid the American's finally responding.