He's saying that's in total/spread out, but still seems on the high side. Between a take-home coding challenge (2h?), online coding challenge (1h), talking to recruiter/HR/hiring manager (1h), multiple interviews (coding 1h, culture/fit 1h, system design/architecture 1h, whatever 1h), you're already at 8 hours for a lot of places.
I appreciate them even knowing how long a person would spend on their interview process though.