"sustainable" was incorrectly translated from the Swedish "miljövänliga" which instead means "environmentally-friendly" ("sustainable" is "hållbar" in Swedish)
The article is about people trying to engineer electronic devices that take into account their full lifecycle?
The knee-jerk cynical "hot takes" on this site are getting really tiresome. It's intellectual cowardice and laziness. Anyone can say this sort of zero-calorie edgy nonsense
I came back to say pretty much that. Since these buzzwords as used in most of society today barely mean anything at all, the writer was probably happy enough to namecheck something vaguely positive and endorsed to do with environment stuff.
It would have tickled my funny bone if they'd gone with "Green" in this case.
(Thanks nonetheless to ilove_banh_mi, for setting the record straight)
It just means that you can continue indefinitely with no end in sight. End could come from financial problems, consumer preferences to help the environment, environmental regulations, supply chain issues, and all sorts of other things.
It's like the sustain pedal on a piano: nothing actively dampens the sound, so the sound will continue for quite a while longer than is typically required.