> Are there any cameras out there that output real raw data from the senors?
I suspect not, because the data output rate from a high end sensor can easily be 32 Gbps, and I don't think any phones have fast enough flash storage to write data at 32Gbps.
You have to process the data in mostly-realtime or lose the data. Storing it isn't an option.
Full sized cameras do use a buffer to deal with burst activity, take series if shots - process - save to slower storage. Also, modern cameras start switching to CFexpress/SDExpress (which are NVMe)
> Version 8.0 was announced on 19 May 2020, with support for two PCIe lanes with an additional row of contacts and PCIe 4.0 transfer rates, for a maximum bandwidth of 3,938 MB/s
Full-sized mirror/mirrorless cameras do that. Sensor is HUGE, optics is very fine and huge as well. Due to how universe works, you can't get similar results with tiny sensor and optics
There's quite a bit of analog and digital post processing and I doubt you can bypass all of it