Not really the intent. Otherwise also using "rage" increases your damage, meaning you get "more powerful", and should not work? It's very clear that the RAI here is to prevent a simulacrum to learn new things, not to prevent it from using regular class abilities.
Honestly I think the intent was to copy an old iconic spell and hope no one has to ever deal with it, because its a horribly powerful broken spell. And when wished: removes the limiting aspects of time and money.
There isn't a way to balance a spell that *almost* doubles your spell slots for the day, and allows a second concentration, and doubles your action economy.
Hell who says you even want to keep a copy of yourself. Maybe you want to go meet a 20 cha paladin and make a sim of them and have a permanent +5 Saves, Protection from evil and good/fear/layonhands bot. Paladin following you around all the time. Or make a duplicate of your monk and have another 4x stun attempts a turn machine. Or you duplicate a Mystic, now its using psi points to basically cast spells, but they aren't spells, (well maybe if wuju).
There isn't a way to box in an ability so powerful as "You get another member of your party forever" and pretend its balanced.