This is a really useful way to think about it, and it lines up with how small businesses have always had to work. When every dollar has to earn its keep, you get very clear about what you actually need before you spend anything — you ask a sharper question, you check the result, and you do not pay twice for the same answer.
I like the point about constraints forcing better thinking, not just cheaper output. Left unchecked, it is easy for any of us to throw money or effort at a problem and call it progress. A budget makes you slow down and decide what good actually looks like first.
The idea of a cost guardrail for teams is a good one, too. Thanks for laying out the trade-offs so clearly.