In my dictionary, a trojan is any malicious software that is hidden inside useful software, no matter what it does.
Typically they do, the infrastructure is there with automatic updates and C&C-like abilities. The driver runs close to the kernel to be able to use hooks into files closing and so on, at least on MICROS~1 operating systems.
Did the Crowdstrike thing earlier this year reach you? They sell a corporate version of this kind of trojan, and did a fuckup in an update, suddenly making a lot of people realise that someone else has control over their computers.
I read the original comment as hyperbole. But can see why it was confusing.
Edit: that came out way more condescending than I intentended
(In my dictionary, trojan allows remote control. Maybe I'm just old.)