I never lag like this tbh. Ping is limited visually to 1000 i believe so idk how you know its 1200 also in uefn/creative islands there can be issues with vehicle spawners and the amount placed this does increase ping for some reason and has been reported. The only other thing could be your connected to the wrong server ?
I have 1gb/s internet and again never lag tbh ping is between 15-27 and im in the uk so i think this is average for my location.
When i join some creative islands ping can go to 60-80 but again this is probs due to devices ie vehicle spawner limits and again this has been reported