Here is a more likely scenario.

In the entire history of more than 20+ years having the exact same email account, which is used for this place, on average my daily spam has never been higher than 10 ....
10 pieces of garbage I had to flush away on a daily basis.

I JUST flushed my daily spam folder in my email now...
with a count of 259 pieces of spam.
Never ever ever have I had to deal with anything of that magnitude.
I think our fictitious "guests" had a reason and I don't believe they were here to "help" us by "ghosting" us.
They came, found ways around things here,
got info on us,
and are using it.

That seems far more likely than 15 000 hollow earth- living maemo devs.