Update: Factory re-set the Archer AX55 Pro router. Tested speed on PS5 (as above - wired) - now I get 918 Mbps down, 111 Mbps up. I have been doing some reading, that apparently the low upload speed...

Got the Archer AX55 Pro a few days ago. However struggling with it on some devices. Laptops/Computers are all running blitzy fast as expected (both wired and wireless). Have PS5 connected to this...