It seems that git annex status is much slower than git status, at least in direct mode. The man page does not give any hint about why it should be slower.

Does git annex status do something that git status does not?

Here is an example in a repo with 8000+ files in direct mode and with no modified files:

$ time git -c core.bare=false status --porcelain > /dev/null

real   0m0.096s
user   0m0.042s
sys    0m0.071s

$ time git annex status

real   0m17.144s
user   0m10.555s
sys    0m1.934s

It is strange to see that git annex status is ~200 times slower than the bare git status.