This is exactly my struggle as a CTO in a non-tech company. The comp & ben budget I'm operating off of started taking shape 18+ months ago and is now "locked-in". It's not only overcoming non-technical CEO's as you're also having to convince your other non-technical peers that Tech should be the exception. The best "evidence" most CEOs and CFOs will accept is outdated aggregated market data that can't be accurately sliced for applicable skils.

I've had to knowingly let attrition happen to prove a point.

If you can't change your company, change your company I guess.