Earlier quoted context omitted.
Wires, flash, and resistors can be replaced
These are part of the chip, thus microscopic and very inaccessible. There are some good images here[1] of various such fuses, both pristine and blown. Here's[2] a more detailed writeup examining one type. It's not something you fix with a soldering iron. [1]: https://semiengineering.com/the-benefits-of-antifuse-otp/ [2]: https://www.eetimes.com/a-look-at-metal-efuses/
https://arstechnica.com/civis/threads/how-did-you-unlock-you...
Some folks even got this working with only a pencil, haha.
Nowadays, silicon designers have found highly effective ways to close off these hacking avenues, with techniques, such as the microscopic, nearly invisible, and as parent post mentions, totally inaccessible e-fuses.
[0] https://upload.wikimedia.org/wikipedia/commons/7/7c/KL_AMD_A...
[1] https://en.wikichip.org/w/images/a/af/Atlhon_MP_%28.13_micro...