BYD didn’t really differentiate itself until starting 2019, which is about a year after Tesla would have had to complete its forced technology transfer program to establish Tesla Shanghai. BYDs first new generation EV concept car in 2019, and production of the Seal and other major EV products (which looks like clones of Model 3s, etc) didn’t start in earnest until 2022. They changed their logo to be a stylistic copy of the Tesla logo in 2022.
Yes, their bus and ICE lines long predated, and they had hybrids built out of forced technology transfers from Toyota. But their EV lines that are so popular didn’t start until after Tesla acquired their corporate license and rights to build their gigafactory. If you’ve done business in China you know forced technology transfers and training of competitive local workforces is contingent on those stages. The factory itself and its parts supply chain would also have required transfer of technical knowledge, skill, and local supplier ability without exclusivity.
It’s not a knock on Chinese people to say the Chinese government is intertwined in Chinese industry (it is communist after all and ultimately the means of production is a public trust), or that there is no “fairness” by western standards in Chinese industry and governmental influence. But it’s also disingenuous to believe BYD pivoted to a full on global Tesla competitor in 4 years from being a low end hybrid and bus manufacturer based purely on their tenacity and innovation, neither of which is BYD known for in its history (having been propped up as a money loser for decades by the government and facing a lot of intellectual property lawsuits from Toyota, Mercedes, Renault, and others throughout its history). It’s too implausible to take seriously and there’s no reason to be credulous.