I had a similar experience moving into a new apartment that had ethernet sockets in all the walls. Took me a while to realize that the cables connecting the sockets up were oldschool Cat5 (100Mbps max) cable, so even though I was plugging Cat6a into the wall it didn’t do a lick of good. Wi-Fi 6 on the other hand is giving me a little under 1Gbps.
I wired up my office, and when I speed tested it, the shitty Ethernet adapter in my USB-C dock was slightly slower than just using wifi.
I had a similar experience moving into a new apartment that had ethernet sockets in all the walls. Took me a while to realize that the cables connecting the sockets up were oldschool Cat5 (100Mbps max) cable, so even though I was plugging Cat6a into the wall it didn’t do a lick of good. Wi-Fi 6 on the other hand is giving me a little under 1Gbps.
You can pretty reliably pull 1G with cat 5 over household distances (10m or so). More likely it’s the equipment limiting the speed.