This is the log from the RPi3+ (wifi) to the LG TV (wifi):
PING 192.168.178.33 (192.168.178.33): 56 data bytes
64 bytes from 192.168.178.33: seq=0 ttl=63 time=4044.905 ms
64 bytes from 192.168.178.33: seq=1 ttl=63 time=3044.612 ms
64 bytes from 192.168.178.33: seq=2 ttl=63 time=2045.300 ms
64 bytes from 192.168.178.33: seq=3 ttl=63 time=1044.963 ms
64 bytes from 192.168.178.33: seq=4 ttl=63 time=44.617 ms
64 bytes from 192.168.178.33: seq=5 ttl=63 time=2009.515 ms
64 bytes from 192.168.178.33: seq=6 ttl=63 time=1010.098 ms
64 bytes from 192.168.178.33: seq=7 ttl=63 time=10.365 ms
64 bytes from 192.168.178.33: seq=8 ttl=63 time=1976.438 ms
64 bytes from 192.168.178.33: seq=9 ttl=63 time=977.442 ms
64 bytes from 192.168.178.33: seq=11 ttl=63 time=1946.443 ms
64 bytes from 192.168.178.33: seq=12 ttl=63 time=945.973 ms
64 bytes from 192.168.178.33: seq=13 ttl=63 time=4855.242 ms
64 bytes from 192.168.178.33: seq=14 ttl=63 time=3855.085 ms
64 bytes from 192.168.178.33: seq=15 ttl=63 time=2854.715 ms
64 bytes from 192.168.178.33: seq=16 ttl=63 time=1859.226 ms
64 bytes from 192.168.178.33: seq=17 ttl=63 time=859.286 ms
64 bytes from 192.168.178.33: seq=19 ttl=63 time=1822.735 ms
64 bytes from 192.168.178.33: seq=20 ttl=63 time=822.433 ms
64 bytes from 192.168.178.33: seq=21 ttl=63 time=2791.693 ms
64 bytes from 192.168.178.33: seq=22 ttl=63 time=1791.383 ms
64 bytes from 192.168.178.33: seq=23 ttl=63 time=791.076 ms
64 bytes from 192.168.178.33: seq=24 ttl=63 time=1469.410 ms
64 bytes from 192.168.178.33: seq=25 ttl=63 time=470.566 ms
64 bytes from 192.168.178.33: seq=26 ttl=63 time=124.394 ms
64 bytes from 192.168.178.33: seq=27 ttl=63 time=1803.786 ms
64 bytes from 192.168.178.33: seq=28 ttl=63 time=803.563 ms
64 bytes from 192.168.178.33: seq=29 ttl=63 time=2774.839 ms
64 bytes from 192.168.178.33: seq=30 ttl=63 time=1774.283 ms
64 bytes from 192.168.178.33: seq=31 ttl=63 time=773.691 ms
64 bytes from 192.168.178.33: seq=32 ttl=63 time=2746.842 ms
64 bytes from 192.168.178.33: seq=33 ttl=63 time=1746.576 ms
64 bytes from 192.168.178.33: seq=34 ttl=63 time=746.261 ms
64 bytes from 192.168.178.33: seq=35 ttl=63 time=2705.372 ms
64 bytes from 192.168.178.33: seq=36 ttl=63 time=1705.448 ms
64 bytes from 192.168.178.33: seq=37 ttl=63 time=705.247 ms
64 bytes from 192.168.178.33: seq=38 ttl=63 time=1513.570 ms
64 bytes from 192.168.178.33: seq=39 ttl=63 time=513.261 ms
64 bytes from 192.168.178.33: seq=40 ttl=63 time=750.958 ms
64 bytes from 192.168.178.33: seq=41 ttl=63 time=23.937 ms
64 bytes from 192.168.178.33: seq=42 ttl=63 time=1992.435 ms
64 bytes from 192.168.178.33: seq=43 ttl=63 time=992.057 ms
64 bytes from 192.168.178.33: seq=44 ttl=63 time=6.340 ms
64 bytes from 192.168.178.33: seq=45 ttl=63 time=1960.692 ms
64 bytes from 192.168.178.33: seq=46 ttl=63 time=960.790 ms
64 bytes from 192.168.178.33: seq=48 ttl=63 time=700.101 ms
64 bytes from 192.168.178.33: seq=49 ttl=63 time=2668.613 ms
64 bytes from 192.168.178.33: seq=50 ttl=63 time=1668.567 ms
64 bytes from 192.168.178.33: seq=51 ttl=63 time=668.383 ms
64 bytes from 192.168.178.33: seq=52 ttl=63 time=2648.888 ms
64 bytes from 192.168.178.33: seq=53 ttl=63 time=1648.650 ms
64 bytes from 192.168.178.33: seq=54 ttl=63 time=648.400 ms
64 bytes from 192.168.178.33: seq=55 ttl=63 time=2616.027 ms
64 bytes from 192.168.178.33: seq=56 ttl=63 time=1615.903 ms
64 bytes from 192.168.178.33: seq=57 ttl=63 time=615.644 ms
64 bytes from 192.168.178.33: seq=58 ttl=63 time=2584.335 ms
64 bytes from 192.168.178.33: seq=59 ttl=63 time=1584.704 ms
64 bytes from 192.168.178.33: seq=60 ttl=63 time=584.705 ms
64 bytes from 192.168.178.33: seq=61 ttl=63 time=2555.403 ms
64 bytes from 192.168.178.33: seq=62 ttl=63 time=1556.464 ms
64 bytes from 192.168.178.33: seq=63 ttl=63 time=556.735 ms
64 bytes from 192.168.178.33: seq=64 ttl=63 time=2523.475 ms
64 bytes from 192.168.178.33: seq=65 ttl=63 time=1523.526 ms
64 bytes from 192.168.178.33: seq=66 ttl=63 time=523.170 ms
64 bytes from 192.168.178.33: seq=67 ttl=63 time=755.846 ms
64 bytes from 192.168.178.33: seq=68 ttl=63 time=2730.547 ms
64 bytes from 192.168.178.33: seq=69 ttl=63 time=1730.313 ms
64 bytes from 192.168.178.33: seq=70 ttl=63 time=729.984 ms
64 bytes from 192.168.178.33: seq=71 ttl=63 time=2712.470 ms
64 bytes from 192.168.178.33: seq=72 ttl=63 time=1712.072 ms
64 bytes from 192.168.178.33: seq=73 ttl=63 time=711.562 ms
^C
--- 192.168.178.33 ping statistics ---
77 packets transmitted, 71 packets received, 7% packet loss
round-trip min/avg/max = 6.340/1563.976/4855.242 ms
Weird, the numbers seems to be quite high. Other devices in the wifi network located in the same room show much smaller numbers.