You may be approx 180m from the fibre cabinet "as the crow flies" but who knows what route the copper (or ali.) cable takes, very hard to tell especially if underground distribution.
From your reported DS attenuation (21.6dB) and comparing this to my line and my daughters line which I monitor, I would think that your DS synch speed is likely as good as it gets for that line length, of course the "cross talk" factor on your line will be unique to you and will certainly be influential regarding the max. DS synch speed obtainable.
Looking as DS INP (52) I would guess that the line is on DS G.Inp re-tx high profile which will decrease the DLM BRAS IP profile and result in a lower data throughput speed for any given DS synch speed.
From my own experience, have found that US synch speeds attainable are more unpredictable and of course very much unique to each line.
For example, my line is comparable length to my daughters line but much better quality, minimal noise & error rates, however, I can only manage approx 5 Mbps US synch rate and she achieves close to 8 Mbps US synch.!
We are both on 40/10 service, different DSLAM's & ISDP's.
Despite her very poor quality, high noise line our DS synch speeds are very similar.
Thanks Tiffy, I also note the upstream bands U2,U3,U4 are missing in my pbParams output - is that also an indication that there is crosstalk on upload (that the DSLAM as opted not to use those frequencies ?)
xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 1
Last initialization procedure status: 0
Max: Upstream rate = 6740 Kbps, Downstream rate = 59212 Kbps
Bearer: 0, Upstream rate = 6740 Kbps, Downstream rate = 59895 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Discovery Phase (Initial) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3970)
Medley Phase (Final) Band Plan
US: (7,32) (871,1205)
DS: (33,859) (1216,1961) (2793,3970)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 6740 kbps 59212 kbps
Actual Aggregate Tx Power: - 7.8 dBm 12.9 dBm
====================================================================================
VDSL Band Status U0 U1 U2 U3 U4 D1 D2 D3
Line Attenuation(dB): 6.3 34.7 N/A N/A N/A 16.4 43.2 67.5
Signal Attenuation(dB): 6.3 33.4 N/A N/A N/A 24.3 42.8 68.1
SNR Margin(dB): 6.1 6.3 N/A N/A N/A 3.2 3.1 3.0
TX Power(dBm): -18.6 -8.2 N/A N/A N/A 9.4 7.7 7.0