This dependency on external providers is unavoidable, Debian
definitely cannot afford to run our own CDN at the scale needed to
support our existing userbase. For example the security mirrors
struggled with Linux kernel security updates, so security.d.o switched
to a commercial CDN. Also, we are dependent on continued sponsorship
for all of our infrastructure, paying for all of our hosting is likely
not feasible.
Personally I'd like to see a larger variety of Debian delivery
mechanisms; copy Debian/snapshot to archive.org, create a multi-distro
FLOSS CDN, bring back httpredir, DebTorrent and apt-p2p, add an i2p
mirror, use IPFS and content oriented networking etc. Michael Stone's
apt://debian idea seems like a good way to move in that direction
while adding protocol agility.