Can you be more specific about what S178 you're referring to? There were several results.
https://www.law.cornell.edu/uscode/text/26/174
As a TLDR it's a way to amortize taxes for R&D over 5 years. High interest rates hit everyone, but this was a sneaky little code that would more specifically hit places like Software.
setup to end in 2022 by the first trump administration, it was one of those "well they'll just renew it, right? And then they... Didn't. So yeah, 2022-2025 made it cost a lot more to hire SWEs than usual.
The only silver lining of the "One Big Beautiful Bill" is that it ended up bringing back S174 for domestic labor. But companies are quick to tear down (and still have half a dozen reasons to tear down) and slow to build back up.