I fully agree.
The older son represents the Pharisees. They never left the father's house in an open rebellion and riotous living in a squandering of the inheritance.
The Prodigal Son represents the tax collectors and prostitutes. They are the ones who turned away and squandered the inheritance. And they are the ones who came back home at the preaching of John the Baptist.
"Jesus said to them, “Truly I tell you, the tax collectors and the prostitutes are entering the kingdom of God ahead of you. 32For John came to you to show you the way of righteousness, and you did not believe him, but the tax collectors and the prostitutes did. And even after you saw this, you did not repent and believe him." (Matthew 21:31-32 NASB)
The Prodigal Son represents the tax collectors and prostitutes. They are the ones who turned away and squandered the inheritance. And they are the ones who came back home at the preaching of John the Baptist.
"Jesus said to them, “Truly I tell you, the tax collectors and the prostitutes are entering the kingdom of God ahead of you. 32For John came to you to show you the way of righteousness, and you did not believe him, but the tax collectors and the prostitutes did. And even after you saw this, you did not repent and believe him." (Matthew 21:31-32 NASB)