slow download through git-annex from datasets.datalad.org

[bpinsard]

For a long time, I had observed that fetching large containers was slow (drops to 2MB/s).
However, it is only through git-annex, direct download from the website has acceptable bandwidth (~50MB/s).

Puzzlingly, testing with wget with the annex object URL and with the path URL gives very different transfer rates (interrupted but just to show an example):

$ wget datasets.datalad.org/repronim/containers/.git/annex/objects/gG/32/MD5E-s3238199296--b77879e14b03c4f13ffa0138b37f2014.1.sif/MD5E-s3238199296--b77879e14b03c4f13ffa0138b37f2014.1.sif
--2025-12-29 21:32:44--  http://datasets.datalad.org/repronim/containers/.git/annex/objects/gG/32/MD5E-s3238199296--b77879e14b03c4f13ffa0138b37f2014.1.sif/MD5E-s3238199296--b77879e14b03c4f13ffa0138b37f2014.1.sif
Resolving datasets.datalad.org (datasets.datalad.org)... 129.170.233.11
Connecting to datasets.datalad.org (datasets.datalad.org)|129.170.233.11|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 3238199296 (3.0G)
Saving to: ‘MD5E-s3238199296--b77879e14b03c4f13ffa0138b37f2014.1.sif’

-b77879e14b03c4f13ffa0138b37f   0%[                                                 ]  14.94M  1.61MB/s    eta 22m 19s^C
bpinsard@elm:~$ wget datasets.datalad.org/repronim/containers/images/bids/bids-nibabies--25.2.1.sif
--2025-12-29 21:33:24--  http://datasets.datalad.org/repronim/containers/images/bids/bids-nibabies--25.2.1.sif
Resolving datasets.datalad.org (datasets.datalad.org)... 129.170.233.11
Connecting to datasets.datalad.org (datasets.datalad.org)|129.170.233.11|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 3238199296 (3.0G)
Saving to: ‘bids-nibabies--25.2.1.sif’

bids-nibabies--25.2.1.sif      35%[================>                                ]   1.07G  44.7MB/s    eta 46s

Not sure if that's only the case for me.
Could it be a webserver config issue?