This is only true in the evolutionary sense -- Example: "parachuting forces people to be good at checking their gear."
Telling someone that they are going to jump out of a plane won't magically give them a skill like meticulousness.
If you have the basics already, so, bootstrapping forces you to build up that. No guarantees, so.
At a smaller company that values its devs, there hopefully shouldn't be too much ceremony around this, unless it's a particularly large spend.
But at larger companies, yes, you're likely going to have to know how to make your case in a more formal way, and get involved in company politics (ugh).
And there should be a good guide for junior devs on how to do that "justify it" step well in startups. Sounds like something that could piggyback off of https://www.kalzumeus.com/2011/10/28/dont-call-yourself-a-pr...
I can't help but think this is a symptom of being awash with VC cash - I can't imagine this happening in a bootstrapped business.