Unless you've purchased phones from all the "more established" brands and verified whether they're sending data, this is hardly sound advice.
"More established" brands have a history of leaving secret backdoors and phoning home just the same as the Chinese devices.
One was discovered in a range of Samsung devices just a couple years ago. Lenovo, same story, spyware and garbage hidden deep within their gadgets.
The only solution is to take a chance, buy a device, test it. If it's backdoored, return it if you can, and call them out on HN/Amazon reviews, etc.
