The biggest expense in software is maintenance. Better software means cheaper maintenance. If you actually want to have a significant cost advantage, software is the way to go. Sadly most business is about sales and marketing and has little to do with the cost or quality of items being sold.

Why wouldn't it move the needle? Less time spent, less frustration, more performance, more resources focused on the business?

You massively underestimate the difference in employee productivity not having to fight user-hostile software every step of the way can make. Not to mention cascading cost savings and infra flexibility distancing yourself from Microsoft products can grant.

It will depend on each case and what makes the marketed solution inferior. If it's overly complex and you will save development time. If it's unstable you'll save debugging time. If it's bloated you will save on hardware costs. Etc...

matters less than we would like it to

after all startups/scaleups/bigtech companies that make a lot of money can run on Python for ages, or make infinite money with Perl scripts (coughaws)

and it matters even less in non-tech companies, because their competition is also 3 incompetent idiots on top of each other in a business suite!

sure, if you are starting a new project fight for good technical fundamentals