>> this software is used to configure the FPGA hardware

> Metal paths on chip dont change in magical way. There is no configuration.

Let's see (emphasis mine):

"A field-programmable gate array (FPGA) is an integrated circuit designed to be configured by a customer or a designer after manufacturing [...]. The FPGA configuration is generally specified using a hardware description language (HDL) [...]. [...] FPGAs contain an array of programmable logic blocks, and a hierarchy of reconfigurable interconnects that allow the blocks to be "wired together", like many logic gates that can be inter-wired in different configurations. Logic blocks can be configured to perform complex combinational functions, or merely simple logic gates like AND and XOR. [...] Once the design and validation process is complete, the binary file generated [...] is used to (re)configure the FPGA."
https://en.wikipedia.org/wiki/Field-programmable_gate_array

"Reconfigurable computing is a computer architecture combining some of the flexibility of software with the high performance of hardware by processing with very flexible high speed computing fabrics like field-programmable gate arrays (FPGAs)."
https://en.wikipedia.org/wiki/Reconfigurable_computing