That would make a lot of creatures dangerously op.
Imagine if a speedster Thor was able to cleanse itself of Distraction or Deceleration, and/or give itself total immunity to it for one turn.
Imagine if Ardentismaxima or Geminititan could cleanse themselves of DoT, and/or give themselves total immunity to it for one turn; Heck, imagine if ANY Resilient could do that, in an already Resilient-dominant meta.
Imagine any Cunning creature suddenly able to give itself immunity to Decel.
And yes, it doesn’t have to be just Decel or Distraction, but that doesn’t matter.
If it’s already got total Resistance or 67% or higher, it could render the move moot since it’s really not gaining much.
If it’s gaining a Resistance that counters a status effect the opposing creature can’t inflict upon your own, it’s just a waste of space.
If it’s gaining a Resistance to the very thing that is supposed to be one of it’s counters, see above.