I'm not minimizing the amount of effort it takes to curate links, but does a mailing list need to constantly grow for it to be viable ? What does it mean to "operate at a loss" in this case ?
Seems obvious that it wasn't generating enough money to make it a viable venture for the person putting in the work.
> The number of advertisers and subscribers has been slowly but steadily decreasing
This does not entail that they need "constant growth" to be viable.
it costs money to send a lot of emails that aren't immediately blocked or sent to the junk folder
My first guess is ESP pricing. Just to pull numbers out of thin air to anchor the conversation, mailing to 20,000 subscribers costs $200–$400/mo at Mailchimp/ConvertKit/Klaviyo, three of the top choices in the space. If it's 50,000 subscribers, that's $380–$800/mo.