This article regurgitates a bunch of urban legends.
The 100k mile canard is handily refuted by many owners who have handily passed that mileage. In fact, the battery is warranted in California for 150k miles.
And $8k to replace the battery? That’s totally false.
The dealership replacement of a Prius battery with parts and labor was about $8k (circa last summer). I knwo several people that bought a Prius. One guy had a manufacturing defect and the battery had to be replaced. He said it was $8k but covered under warranty to get it fixed. He also said that he is not getting near the mileage he expected. That is probably due to his driving style. Lots of long highway miles with a canoe strapped to the top.
This may have now come down like the halogen headlight bulbs of the late 80's and early 90's. The dealers charged $28 for them and a year later they were $9. I haven't bought one in a long time but I imagine they are lower.