There are a few EDA companies, all with ancient software tools but kept up to date with the changing parameters and algorithms. You use the tools the insurance companies tell you or the mandatory tools of your chip fab suppliers. They use a lot of software tools on your design files you never get to see.

If you want to make better chips, like the low power Apple Silicon for example, you create your own EDA software tools to make the innovation. Creating a new transistor like the CFET [1] means writing new physics simulation tools, for example.

The outdated 1990's and buggy Open Lane software for example limits what kind of RAM transistors you can make or the complexity of your design.

My team makes asynchronous chips, free space optics photonics, ultra dense 2 transistor SRAM, niobium SQF chips, wafer scale integrations. All require bespoke software simulation tools, netlist rewriting tools, cross-reticle stepper exposure software (a software change in a $400 million dollar machine), etc etc. Making hardware near atomic size structures is mostly a software job. Hardware is software crystalized early, Alan Kay quips.

[1] https://www.imec-int.com/en/articles/imec-puts-complementary...