Steps to reproduce:
1) Run /tick rate 1
2) Save and quit
3) Run /tick query
The tick rate is set to 20 again
Linked issues
is duplicated by 6
MC-266545
When you re-enter a world in which ticks were freeze, the ticks are unfreeze
Resolved
MC-267516
The /tick Command Always Resets When You Re-Load The World
Resolved
MC-268653
/tick command effects don't persist upon game restart
Resolved
MC-270956
Time is getting faster, and the end teleportation gate screen is also changing.
Resolved
MC-275169
/tick command breaks when reloading a world
Resolved
1 more links
I dont believe that this is a feature for auto saving tick rates and reloading them.