Ethernet cables can be as long as 100meters, long enough to snake around most any apartment. Add on a few rugs to cover over where they'd be tripping hazards and you're all set.
In an apartment I once had, I ran some cat5-ish cable through the back wall of one closet and into another.
In between those closets was a bathroom, with a bathtub.
I fished the cable through the void of the bathtub's internals.
Spanning a space like this is not too hard to do with a tape measure, some cheap fiberglass rods, a metal coat hanger, and an apt helper.
Or these days, a person can replace the helper by plugging a $20 endoscope camera into their pocket supercomputer. They usually come with a hook that can be attached, or different hooks can be fashioned and taped on. It takes patience, but it can go pretty quickly. In my experience, most of the time is spent just trying to wrap one's brain around working in 3 dimensions while seeing through a 2-dimensional endoscope camera that doesn't know which way is up, which is a bit of a mindfuck at first.
Anyway, just use the camera to grab the rod or the ball of string pushed in with the rod or whatever. Worst-case: If a single tiny thread can make it from A to B, then that thread can pull in a somewhat-larger string, and that string can finally pull in a cable.
(Situations vary, but I never heard a word about these little holes in the closets that I left behind when I moved out, just as I also didn't hear anything about any of the other little holes I'd left from things like hanging up artwork or office garb.)
I assumed to get from one side of a doorframe to the other, instead of crossing underneath the door, go around the perimeter of the room the door is for. Which seems like a lot to remove a trip hazard, but I suspect the Wife Approval Factor plays a role
the one sort of asterisk I'd put there is that ethernet cable damage is a real risk. Lots of stories of people just replacing cables they have used for a while and seeing improvements.
But if you can pull it off (or even better, move your router closest to the most annoying thing and work from there!), excellent
