Are there really 5+ day nonstop playthroughs? Are there just hours of no content while the streamer eats/sleeps? Why wouldn't that be split into multiple parts by the streamer, as a natural consequence of how it was recorded?
So you'd hit the limit after 600 ten-minute videos, or 100 hour-long videos.
The limit also seems to apply to "Highlights" and "Uploads" but not to "Past Broadcasts", "VODs" or "Clips" for added confusion.
One might imagine this is just the logical followup of them adding that horizon initially, basically saying "the 1 in 200 of you who circumvented our policy, no, for real, stop that."