it wasn't in deep freeze, just in the back of the fridge.
it is very hard to kill a sourdough starter as long as it's established. I think of this video where he sets his sourdough starter on the kitchen counter (room temp) for THREE WEEKS 👀 while he went on vacation. he revived it and baked with it no problem.
it does take quite a bit of commitment in the beginning to get it going though. I think it took me like a month of persistence to get it mature and active enough to bake with.