Yes she can. People think Phoenix is this unbeatable god-like character bc of Dark Phoenix but this has always been a false view of Jean and her abilities. Dark Phoenix eating a star was an exception; it was never her norm. Claremont wrote Jean with clear limitations when she got her Phoenix upgrade
Her power was finite. She was able to do amazing things but if she overexerted herself, she'd weaken herself. Magneto used this advantage to defeat her and later after saving she and Beast, she passed out. Heck the way Xorn killed Jean isnt unlike what Magneto did to her here, except he of course held back
Proteus defeated her and it took Colossus of all people to save the day
This notion that Jean cant be Phoenix bc of the types of enemies the X-men face, just doesnt hold up. Yes the concept of Phoenix has changed since then but thats a fault of the writers. The ironic thing is that Jean sans PF grew to be almost as powerful as she was at her base levels during Claremont's run. Jean doesnt need the Phoenix Force to be powerful not does her having it make her too powerful. She needs it bc its part of her iconic imagery and brand and shouldnt be viewed as either a crutch or limitation