Spam in the lists out of control
The level of spam in the lists is something like 20% these days [*].
Those who still do not see the need to make the lists closed for non
subscribers or non registered people (via the whitelist), please
propose a better solution.
The current level of spam is not acceptable by any standard,
so "do nothing" does not count as a "solution".
[*] Examples, for the lists I'm subscribed to:
86 junk messages and 440 good messages yesterday.
76 junk messages and 200 good messages today.