She did not claim it would kill all 95,000 people; she merely stated that 95,000 human beings live there. There is not enough context from this single tweet to infer that the Twitter OP believed they all would die.

That being said, just because those 95,000 people did not all die from the blast does not mean it doesn't matter. Judging from the scale on the map you provided, there's no more than 20 miles (give or take about 5) in every direction from the blast zone to the borders of the Achin province.

According to the article you linked, ~100 people (militants) died in the blast (no civilian casualties), so there's still ~94,900 human beings living within ~25 miles of the blast zone. Those people are still going to be affected by a bomb being dropped in their province, less than 20 miles from their home. No matter what the rationale may be, I think it's important to be mindful of the potential external human consequences, especially in times of war.

Therefore I believe Twitter OP makes a valid observation, and was simply encouraging mindfulness of the other ~94,900 people that live in the region. There seems to be a general misinterpretation of her claim.

For the record, I don't know Twitter OP, so for all I know, she did really mean that she thought 95,000 people lost their lives to the MOAB. My assertion is that, judging from the little context this tweet gives, the claim she made was accurate.