WiFi extends WiFi, not hard wire..
Cat 8 is some great stuff. Great terminal ends. Very tight connection and very good individual wire separation. I tore a cable apart and looked. I paid 10.00 usd for the cable.. It was a ribbon, thick insulation, the terminal ends are really well shielded just like the cable.. I went from CAT 5 to Cat 8.. Everything is better with a 14.00 cable change..
Neither cable ever had errors, BUT a serious speed increase though.
I ran one at 10 feet one at 25 feet, one at 50 feet to the back room..
It’s a co-axel to the box.. Router to laptops use Cat 8 now... A 100% increase in download and 50% increase in upload, with all 3 runs . Bidirectional protocol.
Regards