I shouldn’t have generalized that statement. There are some exceptions with brain fields like genius ofcourse which are kind of optimised for half day use or older 2 hrs usage per day limitations.
Of late, Dream fields are more powerful and direct in action. These physical affect fields can wreck the system if used 24*7 as a tag. There could be exception and it’s basically depends on how dream optimise it for daily use.
Most of the physical fields are not meant or designed for that imo.