A normal copy consists of a program reading from one file and writing to another. There is no way for the filesystem to do a reflink in that case, it just sees that the program is reading and writing stuff. In order to do a reflink, the program must tell the filesystem what data should be "copied" to where using FICLONE or FICLONERANGE. Though some programs will do that by default if possible nowadays when copying files or when moving files between different subvolumes on the same partition, including the Coreutils cp, mv and install commands and some GUI file managers.
LaggyKar
Yes, using KDE Connect, which has had this functionality for ages. Though you're best off using the F-Droid version since Google has severely limited the Play Store version using SAF. Seems like they've they've given Microsoft a pass here even though they've blocked KDE Connect from doing the exact same thing for years.
Where's the part where he suffers?
It's 401 unauthorized or 403 forbidden, not 403 unauthorized
Harvesting IP addresses shouldn't be a problem, since the firewall shouldn't allow packets from a peer you haven't talked to first. But true, if you can be attacked in response by a server you're connecting to that would be bad.
This would presumably mainly be an issue for computers open to the internet. So not so much for home PCs, unless the router's firewall is opened up.
How would that bypass the firewall?
This TV Streamer costs significantly more than a CCwGTV combined with an adapter.
None of which changes the fact that it's more expensive and clunkier, and none of which feels necessary.
You can get an Ethernet adapter for the Chromecast
A more expensive, clunkier product, with a bunch of needless fluff in it.
One thing that you do still need root for however is proper backups. The built-in backup system is tied to Google, and it's very limited in what it will back up, nowhere near what you can do with root backup software like Titanium Backup.