I suspect the biggest barrier to most homeowners running Ethernet besides not knowing that it’s not that difficult is insulated walls. Running some cables through walls without insulation to the attic and making some drops is not problem, but if you have insulation in the way the job is a lot more difficult.
I do acknowledge that there are many small (big) barriers.
I am on my second home, the first was a condo where I had no access to the "above" or the "below", only the "within".
Phone lines had been run, so I thought I could attach Cat5 to the phone lines and pull them through -- but the previous owner had decided to wall up the phone jacks. No idea where they were, and no access to the "above" part.
Let's just say - I tried a lot of things to figure out where the walled up phone lines were, but never could get to the level of confidence you would want before you start knocking random holes in the wall in a property you own.
Powerline Ethernet was a godsend - for a while. Then one day (7ish years) it started struggling, and eventually couldn't stay connected. To untangle that was going to be hundreds of dollars of hardware and research and/or contractors (side note: have you tried asking an electrician to assess Powerline Ethernet issues?) -- I went wireless at that point.
New house maybe a year back after getting married (yay!). Ran ethernet. Used these guys:
Yeah, I drilled some holes in the wood floor. I am not that rich, nor is my neighborhood, it's a non-issue. Game consoles, NAS devices and work computers have ethernet. Everything else less hungry (or important) like a tablet or mobile has wireless. Life is good.
