Rob... I'm sure you are aware that there are very clear distinctions between offering network, email, web, voip, ntp and the many other services that make up what we consider to be the internet today?
All these parts are put together with varying levels of skill, resources, hardware and service-specific expertise. 44net (AMPR, ARDC etc) offer network services, they are an NSP, the people that would for the organisation and provide the service, although may well be inclined and skilled in such a way to rebuild a mail server, they are not mail-service providers. The mailing list is ancillary to their core-service, as such they felt the best thing to do now is perhaps find a provider, that has a core-competency in mailing list management.
It is for the users of 44net to make-up the services that reside on the 44net service and if the person that volunteered their time, resources and effort into maintaining a now defunct mail-server now decides he no longer wishes to do so, it makes perfect sense that what is considered an incredibly well-used resource is hosted elsewhere, where any of the previous oversights, such as backups, will be maintained under an SLA with a provider who offer those services.
I've worked with the amateur radio community long enough to know that the callsign comes with a sense of 'entitlement' that empowers its holders to almost 'demand' the free services they are using not only continue to be free indefinately (doable) but also in such a way that appeases them (not so much)... If you feel so strongly that in the spirit of ham radio that someone volunteer their time, resources and effort in to hosting a mailman service.... you do it!
I'm an IT professional, I could host the service quite easily at my QTH or on one of the VPS I have, but I have to ensure that user data is protected and secure, isn't succumbed to cyber-offenses and that the service has a reasonable level of availability and it's usage conforms to the many regulartory domains that exist across the world... Doing to for free, doesn't negate liability by the way ;) So, I passed on the opportunity to raise my hand... and anyone else considering it needs to read the above first.
Thats my 2-pence... ;)