Wifi speed looks pretty normal for a MacPro that sits within 5 meters from the modem, in a building with lots of neighbours near. 802.11ac can do better, but requires a better wifi station and preferably less to no neighbours.
The upload test result looks like what you can expect from a wifi 802.11ac connection at 585Mbps (MCS7 - 2).
However the download speed is indeed low. Since your upload looks fine, I assume that there's nothing wrong with your wifi card inside the Mac and the wifi modem.
It looks more like that the cause is in the fibre network. If you have a GPON fibre connection you share the fibre connection (and its bandwidth) with 16 to 64 other subscribers. Only the network provider knows this number, but if for example there are 16 subscribers on the same fibre, all downloading at full speed at the same time, the actual attainable download speed is around 150Mbps per user. Now, this is the worst case scenario but it is worthwhile to do the speedtest on different hours of the day. If the download speed remains this low all day long, including at 03.00 in the morning, then you have to contact Vodafone for further network check.