this is not the point of this, the first point i was talking about is how you said you play on a paper citybuild server running 1.16.4 (laggiest version of minecraft to date) with 10 players and most of the time achieve 20 tps when someone with an empty server and no chunks loaded and no mobs no players cant achieve 20 tps, there is a clear difference here, probably to do with mod servers, anyway, the second point is the 5 tps when loading chunks, thats not normal, nothing in the logs, reported it before alot even on the discord, got 0 help, all what i was doing is playing on a paper server alone loading chunks in the overworld by just sprinting normally like any player would do and then i noticed i was rubber banding like heck so i just typed /tps and got the number 5, also its def not my internet, even if it was my internet the tps is the point here not the rubber banding.
anyway tho i managed to solve this problem by using fabric lithium and phosfor and not updating to the laggiest version of mc (at that time i was running 1.16.1, and even now im limiting myself to 1.16.3 which is a bit less laggy than 1.16.4)
another thing is on that exact same server i have huge problems in the nether and i explained it in its own thread (its recent so i didnt get a reply yet).
forgot to mention the fact that my pc stays permanently at 60 fps even when running a benchmark to check for problems (which i explained in the nether problem thread)