Don’t overlook the OS default options. Quick Assist in Windows 10+, Facetime can screenshare in MacOS/iOS devices. Not sure if there’s an android comparable.
If you are running chromebooks or linux for family users then it makes sense to install a client.
In my experience, this mitigates the issue of you managing software on devices and allows you to support even new/remote devices.
This assumes you’re only doing ad-hoc support, and not making sure they are applying windows updates or maintaining other software updates on their behalf (which I do for my parents every 4th of July and Christmas gathering, everyone else can deal with their own).
I mentioned that you should consider if you want your support system on the same infra as the system that could be an issue. Creates a catch 22, but you could look at HESK. Simple, email flow. It’s SysAids free thing. It itself I don’t know if it’s dockerized, but you pull a simple nginx/apache+php install, setup a db container (it may support sqlite, can’t remember) and you’re golden.