And they've provided no technical explanation of how...

This may be an odd reference, but I remember this song and dance with Roomba Vs. Roborock. "Roborock stole our IP!!!" but the problem was that song was slightly believable in the very early days, then Roborock started releasing products far better than anything Roomba had, but the tune in the US never changed. Literally for years after Roborock's products were two generations better than Roomba, but somehow they "stole" that?

China has money, talent, and cheap electricity/superior infrastructure. The US's big AI built their products on stolen copyright material and social media scraping. China likely got a catchup boost via distilling, but recently a lot of their AI ventures have come fully online, and they've just throwing tons of compute/power at the problem, and we're starting to see legitimately competitive products without shortcuts/cheating.

But the US won't change its tune; and that's convenient because they don't really want to compete, but rather roll out protectionism and fear per normal.