Rather, it's that the mechanism is only offered as a standardized way for a
browser to request a feature that already exists in a number of major sites.
And that's precisely the problem.
Sites can easily adapt their services to the needs and desires of their users.
They can do it today using site specific settings. I am pretty sure that these
settings require more than just one bit, so we have to assume that sites will
still need these settings tomorrow even if that safe bit proposal was adopted.
There is thus not much engineering benefit. In fact there is probably a cost,
with settings coming from two channels instead of only one.
By creating a standard, we would be creating a social norm. It would not take
long for regulators to mandate "safe" behavior for web sites, or to enforce the
safe bit in various kinds of "great firewalls." It will all be in the name of
protecting the children, but we all know that the real target will be dissent
and free speech. By offering this setting as a standard, the IETF would become
an accomplice of repressive regimes and other religious dictarures.
Some features do not need to be standardized.
-- Christian Huitema