Back in the 1980's there was an entrepreneur named Adam Osborne. He released a portable computer called the Osborne 1. It was large and heavy, but it was the only game in town and had decent sales. The Osborne started talking about more advanced computers that were still six months to a year away. People decided to wait for the more powerful computers rather than buy the one that was currently available. Sales of the Osborne 1 crashed, and the company went under. This became legendary in the tech community as "the Osborne Effect." It is why when Apple announces a new phone they have it shipping within a month.
Last year, every EV manufacturer announced that they were moving to the Tesla charging standard in 2025, and adapters would be available in 2024. So, if someone were to buy a non-Tesla right now they would be using a dying standard (CCS) on an unreliable charging network. Not surprisingly, such buyers are questioning the wisdom of this, and are choosing to wait until the vehicle they buy can use the charging network that is available and works (NACS). It is the Osborne Effect applied to the EV market.
Ford and GM should have at least the adapters available in 2024 Q1 (according to Tesla). It will be interesting to see if after that GM and Ford EV sales deviate from those vendors who do not yet have NACS adapters available. It will also be interesting to see if non-Tesla EV sales pick up when NACS becomes the built in standard for those vehicles in 2025.