Middle Management doesn't really control the purse strings. They can certainly lobby for it and they do. In most companies budget's are allocated at the executive level to each of the departments.
They are positioned critically as information transmitters between high level and low level. As such they are conveniently situated to shape the narrative to flatter themselves, in both directions. No wonder then that so many middle managers blame their underlings and insist they would be good at their job except for the meddling engineers. So of course execs would hear this and think "middle managers deserve more money, engineers need to improve their performance so let's dangle bonuses but not raise their salaries".
I don't think blaming your underlyings is a good strategy even for the mediocre middle manager. That might make work if there is a re-org and your entire org is changed and you inherit a new one.
However, your org is typically the one that you hired, trained, and grew. So, if you are saying that you failed to make the commitments that you promised because your org sucks, then you are just telling everybody that not only did you not fail to meet your commitment you are also not good at building an org.
You can't blame your underlings, if you blame your underlings then people aren't going to think you are doing a good job. If you have any character you will take responsibility and admit that you failed. Then you will work with others to fix the issue, it's not the end of the world.
Now, if you really want to deflect blame, there are many better places to deflect it. You can blame
1. The business/sales/product/external factors ... whatever, they imposed a deadline that was unrealistic. You were brought in too late and you did the best to salvage the situation.
2. A parallel org that you had an external dependency. Bonus points if you compete for budget with this org. If you can successfully deflect blame to those yahoos in the parallel org, then maybe you'll capture some of their budget and get more head count to grow your org. Yes, you want to grow your org. This is another reason why blaming your underlings is a bad idea. Why would you get more budget to grow your org, if you've done a bad job at hiring and training your current org.
In conclusion there are a bunch of bad middle managers out there, and it might be widely thought that blaming the underlings and ICs is a good move. But it's a terrible move for both selfish and selfless reasons. Even bad managers will know that it's a terrible move.
I think it's more that managers seek to maximize their career advantage by having the work done according to "their idea". Then the engineer is just a commodity resource implementing what they are told. And to the degree that this added constraint on the engineer does not fit with their experience or with what would work best (or at all), the engineer's productivity is lower. This is addressed by adding more engineers.
