Some people charge insane prices. I can't believe a foundation issue would cost as much as new construction. It's not that hard to put in a French drain, even if the house needs to be cribbed up due to structural issues.
I know, seems crazy from the outside looking in, but nothing was particularly outrageously priced (and we did get several estimates from all sorts of people). To be fair, it wasn't just the foundation. Because of the mold in the basement the rest of the house also became contaminated and needed to be remediated (and my family is now super sensitive). I will also note that this during COVID so prices were somewhat higher than they are now. Believe me we did not set out to tear down our house, but that ended up being the best way to address the issues with the old house.