The Earth will be habitable after the cataclysms, and this is why the human species has continued through previous cataclysms. Life is rough, and life is short. The infant mortality is horrific. The strong survive, and where there is communal cooperation among caring people, the odds are not really that bad. Habitability varies, depending on location. The poles shift, the winds shift, volcanic eruptions continue from activated volcanoes that take some time to settle down. The rains seem continuous, but plant life does not mind this as much as the mammals trying to get dry. Diets are not as varied as before, as far as staples go, but in other regards are more varied. Those who survive learn to eat everything, including bugs. Bugs are numerous, growing in great numbers in the humidity, and living off the tissue from the dead, which seems to be everywhere.
You must expect the habitability to be equivalent to preparation. Where your government does not inform you of what is coming, and where the establishment fears panic and disruption more than it fears the consequences of not informing you - your preparation will suffer. However, in truth, it will be difficult to prepare. So much will change, and the change is not under human control.
During past cataclysms the human population was also decimated, but as primitive conditions prevailed death from earthquake damage was slight and almost all the survivors were familiar with farming practices. Housing during past cataclysms was light, made of straw or wood or cloth as in tents, and this splintered or blew away during earthquakes rather than landing on and crushing the inhabitants. Unless the humans were unlucky enough to be in the path of a tidal wave or lava flow or standing on heaving or hot earth - they survived. Following past cataclysms the survivors had not much less after the cataclysms than before, as they had been living a bare survival existence as is. Life became harder, of course, as one could plant but would find no harvest and domesticated animals soon died from lack of feed. Fewer and fewer fish were in the streams, fruit and nut trees failed to bear, and produce normally harvested from the wild suffered in like manner. The survivors found themselves faced with having to be resourceful, eating whatever could be found - bark, bugs, moss, leaves, and on occasion each other.
The coming pole shift will differ from past cataclysms in several respects, however, all of which will bode ill for the present human populace.
Consequently, we predict that 90% of the population will die as a direct or indirect result of the cataclysms, with the remainder polarizing due to the increasing polarization of the spiritual orientations. This Aftertime will be different, spiritually as well as physically.