Hadley's Brother

Now thinking of it, that scene and the way it's written seems too modern. In the 1950s when it takes place, $35,000 as you said is a lot more money than it was in 1995 when it came out. Yet the scene is written so that Hadley thinks even after paying taxes on it, he could maybe afford a new car and that's it. In the 1950s it'd cost way less than $20,000 to buy a new car. Yet the way it's written, it acts like $30,000 is only enough to buy a new car and maybe enough to add a tiny bit to repair his house. It's weird on the writer's part like they forgot it took place decades before.

I feel like one of the many great aspects of demonstrating the nature of the characters of the film exists within scenes like this. A lot of the events of the film that lead up to this point do a great job at displaying the humanism of Andy, Red, Brooks, and Red's prison buddies. Even though we have been shown that Hadley is a brutal and harsh man, this scene really shows us how his harsh ways are not merely part of his job - he really is a man with no sense of understanding and he is not capable of things like regret and empathy. Even when one of his fellow guards says he is sorry to hear of his rich brother passing away, Hadley makes it clear that he couldn't care less and is audacious enough to be angry at him for leaving him a decent supply of cash.
I feel like the fact that the Warden is humanized early on (his scene with Andy during the inspection when they both discuss their favorite Bible verses, the scene in his office where he shows Andy the needlepoint picture that his wife made in the church group, etc) really makes it more of a gut punch later in the film when he throws Andy in solitary for a month, has Tommy killed, and adds on another month to Andy's time in solitary. Yet, we know from early on that Hadley is an evil bastard who is capable of carrying out anything with no ethical sense of self control.

You are right.
This happens far to often in order to appeal to the ignorance of modern audiences who not only have NO CLUE about history but refuse to be instructed on it.
Shameful really.
The dumbing down effect.
Not enough to sway from the story but still, one of those little points the keep it from being great.
Would have made more sense for him to have been left his house and the burden of unloading it.

I think Hadley's beef was that 35,000 dollars was a small part of the brother's estate and that Hadley did not understand the tax system very well. Some people in Hadley's position would resent the other portion being purposed for other things even if it was the moral and correct thing to do. As other's said 35,000 dollars was a tremendous amount of money in 1950. Most homes outside of the wealthy sections of Boston, NY, and Philadelphia did not cost 5,000 dollars and most cars under 2,000 dollars. The 1950's was an excellent time for investment in real estate and the stock market. There were quiet millionaires around my locale who invested during that time and never needed to touch that money until retirement.

Agreed that he's an ass about it but by how much? Let's say that Hadley was making $4000 annually*. His federal taxes alone would have been 27%. But at $39000 they would have been at 69%. A pretty big jump.

At $4000 his remaining pay after federal taxes would be $2920.
At 39000 his remaining pay after federal taxes would be $13090

And that's just federal taxes.

So he certainly wasn't set for life. And to inherit nearly 12x your annual post-tax wages and watch it turn into just over 3x your annual post-tax wages just from federal taxes alone is a bit of a rip off. Don't forget that the $13090 amount includes Hadley's annual wage. He's really only inheriting $10,170. I'm pretty sure just about anyone else here would be pissed to find that the government is prospering 2.5x more than they were if they were inheriting the money.

*Google is putting the average family income in 1950 at $3300. Hadley seems to be a bit more than the average guard.

1950 federal income tax rates: https://www.tax-brackets.org/federaltaxtable/1950