Honestly the idea that the level of power you have correlates to your status as a Jedi is basically the philosophy of the dark side. They value physical strength and offense above all when it comes to the force. With the Jedi it’s about far more.

“I shall become more powerful than you can possibly imagine.”

How does that power manifest? In an unstoppable onslaught against the Imperial navy? Nope. Obi-wan’s power in the afterlife transcends the trappings and failings of the material world. His is a power that Vader literally couldn’t imagine - a power that had nothing to do at all with physical strength or attack.

Luke doesn’t truly become a Jedi until he stops fighting and tosses his lightsaber. It wasn’t his physical strength that helped him topple the Empire. It was his compassion. Luke’s greatest force power in ROTJ, the one that makes him a Jedi, and the one that kills the Emperor, is one that has him completely rejecting his own strength in combat that he has developed through rigorous training. And ultimately this is same reason why his actions in TLJ are the greatest we’ve seen any Jedi yet accomplish.

“A Jedi uses the force for knowledge and defense.”

Now what does this have to do with Rey? Well, it just means that, despite all her physical strength in the force (and her apparent skill in combat), we still haven’t seen her face the true test of what it means to be a Jedi. And that matters far more than whether she can already do a mind trick or not.