Earlier quoted context omitted.
The nature of these kinds of errors is that when the error favors Amazon (or whatever company), it's "keep the lights on" mode. If it's the company losing money then alarm bells ring, and it's "all hands on deck" to fix the issue.
OP clarified the opposite here. As former amazon retail I can confirm we commonly lost money to vendors, sellers, and customers. Funny example was prime day promo fat fingered, with several expensive lenses shipped for $99.
In 2020 the German government lowered VAT in a reaction to covid from 19% to 16%.
On the first day Amazon had reduced thousands of products by exactly 19% and only increased by 16% after a few hours. AFAIK they did honor every sale during that time.
I can totally see that happening. Who develops systems with short term VAT changes in mind?
Aldi iirc just kept the old prices and simply gave a 3% discount at checkout