Security updates are still coming. Trisquel 7 is based on Ubuntu 14.04, which
will receive updates until April 2019.
To waste a minimal bandwidth, choose the NetInstall:
https://trisquel.info/en/wiki/using-netinstall-image-bootable-usb-drive
Donations cover infrastructures costs, travel fare for LibrePlanet and the
USB Keys sent to associate members:
https://trisquel.info/en/wiki/financial-information
Quidam has not received any stipend since May 2015. He has certainly deserved
one though.
If you want to help (rather than complaining that quidam does not work
enough), I am pretty sure quidam would be happy to publish a new ISO of
Trisquel 7 if you make one.