quoted

i also dont see any benefit from inlining small files:

quoted

with defaults (inlining small files):
real    4m39.253s
Data: total=10.01GB, used=9.08GB
Metadata, DUP: total=2.00GB, used=992.48MB

quoted

without inline:
real    4m42.085s
Data: total=11.01GB, used=10.85GB
Metadata, DUP: total=1.00GB, used=518.59MB

I suggest you take a closer look at your numbers.

both use 12GiB in total and both need 280 seconds.
am i missing something?

Ahmet