In one sense you made a terrible choice in going with the 77" version of the TV in the first place as this will only exaggerate this issue, I do feel for you that you are one of the many people (but by most accounts not all) that even notice this in the first place.
On a 48" or 55" version of the same panel the issue is practically non-existent just because the scale is so much less
Unfortunately there are pros and cons to every kind of tech out there and as the old saying goes "you pay your money and you take your choice".
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yeah all lg OLEDs are stuck at 100mb which I agree with you in this day and age is nigh on criminal - but to give them credit the wifi onboard is amazing, Im streaming full bitrate 4k over wifi with no issue at all (doesn't excuse the poor LAN port admittedly)
From my experience (worked in IT for 30 years) most home wifi setups are pretty terrible relying on ISP standard bb modem , even fibre modem wifi isn't much better.
I always use fixed cabling if at all possible, its hugely more reliable once its working where as wifi can be affected by environment out of yuour control (like neighbours having a stronger signal in certain areas etc etc and can cost a lot more in certain circumstances to get working well especially if you need 4k bandwidth.