Even that isn't right: if the original balance was $100k the loss can never be larger than that. You still have 25K in the bank so the loss is $75k, any other interpretation should not be labelled a loss, at best they are misguided expectations.
The 150k is a "loss" in the same way that the movie industry "lost" $500 million (or whatever it is that they claimed) to piracy: revenue that they think they should have gotten, but didn't.
I agree it's up to interpretation, but in this scenario, the seller has shipped a set number of goods that the customers have paid for. The revenue has been generated but not moved successfully through a service provider to the final destination.
So it's not just an estimate. The money is not imaginary, it has already been collected from the customers.
You buy the product and ship it, costing you $75k. Your balance is now at $25k.
You expect revenue of $150k from customers. This would take your balance to $175k with net profit of $75k.
But Stripe refunds the customers, and the revenue never comes. Your net loss (excluding labor, marketing etc.) is now either $75k (the money that is no longer in your account) or $150k (expected balance vs. the actual balance).
It doesn't make sense to take the sum of those two. Your expectation was that the incoming revenue would cover the procurement and shipping.