I don't think the mc will end up wealthy through inheritance.
The idea of easy money flies in the face of his dad's upbringing, and is cemented by the example of the other characters in the game:
- Even in the opening prologue to the game, the mc states, they don't have much, but they have each other (he and his dad), they had enough.
- Lynette ran away from money to be with Neil.
- Jill believes that money doesn't bring her the things that make her happy.
- Tybalt thinks he's important because he has come into money, money that he in no way earned (whether he was adopted into the Burke's family like Sage or he was Jade's son from another marriage).
- Rusty squandered his father's money and treated it like it was growing on trees.
- Tommy rides Rusty's coattails, demanding that he make his dad give them more money.
- Jade hates that Stephen can buy his title (honorary professor) and hasn't earned it properly.
- The Royce's strict requirements because they were an "important" family seems to have lead to Lana's death.
And when the DIKs run out of money, they band together, put in hard work, and make something of themselves. Something they can be proud of, and they are proud; they feel good that they earned their new mansion and didn't have Rusty's dad just open his wallet.
So all of these wealthy families: The Burgmeisters, the Royce's, the Burke's, Lynette's dad and so on. None of them are really special, their kids are all fuck ups one way or another. So why would it even matter if the mc was just another wealthy kid?
The mc doesn't care about money, he doesn't even care if Jill's family is famous or wealthy.
And while we are finding out some people are related, like Jill is a Royce, Rusty is a Burgmeister, Sage is a Burke and so on, the theme of the game is not blood family, but the people you hold dear in life, those who support you in the good times and bad:
"Family."
"My dad once told me that a family is more than blood relations."
"Being related doesn't necessarily make you family."
"Family are the people who support you in your choices."
"Family will help you grow."
"Family doesn't give up on you in times of need."
"Family are the ones who love you for you..."
"...whoever that may be."
"Even if you lose your family..."
"...or if your family loses you."
"Don't stop."
"Find new ones to love and somewhere else to call home."
His brothers are the DIKs, his sisters are the HOTs, hell, even Jade is his mommy

, and so on. And these are sisters he can fuck and not get into trouble with Patreon.
No, I don't think the mc will turn out to be a Burke, Burgmeister, Royce or anything else of "importance". He already received his inheritance from his wealthy grandparents, it was a poxy 5K.
Now the rest is up to him.