This has been explained over and over again since 2011 when congress forced NASA into SLS.
Launching a moon mission on standard commercial rockets is absolutely possible. Many different architectures have been proposed to do that. Its really not a question at all.
Its not about 'matching capabilities' because Artemis is currently designed such that it requires SLS. So of course if you design to program to the rocket you were forced to use, then of course its the only option.
When the NASA Administrator in 2019 proposed to shift to Falcon Heavy he was almost fired and was given a mouth guard on the topic. NASA was not allowed to invest single $ into any program that could threaten the existence of SLS/Orion.
NASA is barley even allowed to make studies that suggest an alternative.
Just in very simple terms a few possible architecture:
1. This is if you are forced to keep Orion. You need to change Orion so Orion and a slightly larger Service Module can dock in orbit, rather then launch together. Each one can launch on a Falcon Heavy. This alone would give you 3.5 billion to invest into the service module and other related cost. And over the 2020 would save about 15 billion $ or more.
2. You can throw away both SLS and Orion if you add extension tank into the cargo trunk of Dragon then it could do basically the same as Orion/SM does now. That would literally save 5 billion a year and would easily be enough to make a real service module.
3. The Artemis architecture already requires a moon lander. Instead of SLS/Orion you can launch people into LEO with Crew Dragon or Starliner, there they would transition into the moon lander. And the journey to moon and back would be in the lander.
There are many other way. Almost every other way is cheaper then SLS/Orion. Try to do the math yourself.
But of course the problem is, NASA is simply not allow to advocate or design such missions architectures. Any architecture that cuts out SLS or Orion is stillborn because of politics.