“Over a decade ago, Apple partnered with Intel to design and develop Thunderbolt, and today our customers enjoy the speed and flexibility it brings to every Mac. We remain committed to the future of Thunderbolt and will support it in Macs with Apple silicon.”
The Apple comment comes at the same time Intel has just revealed details about the latest Thunderbolt 4 standards. It’s based on USB-4 and uses the USB-C port that the existing Thunderbolt 3 uses. Apple has said it'll release the first Mac with ARM architecture this year, so presumably it'll support Thunderbolt 3 or 4, or both.
The advantage of Thunderbolt 4 will be that manufacturers have to adhere to certain hardware requirements, such as devices having to support two 4K monitors. It might make for more expensive equipment, but Thunderbolt is preferable when its certified as you know it’s going to work.
This is a major advantage over USB-C, which in reality only guarantees the cable will fit the port – there are so many standards that the port can adopt that it’s often a wild west situation when trying to pair hardware for your setup.
When Apple announced its forthcoming move to its own ARM-powered chips on a Mac by the end of the year, it didn’t address whether Thunderbolt, an Intel standard, would be supported. This confirmation is a positive move from the company, who would have annoyed a lot of its Mac fanbase if it had cut ties with Thunderbolt. It would have rendered a lot of expensive accessories useless on new machines.