they're wrong about a couple things dealing w/ Psylocke.
Psylocke posessed the capacity & willingness to KILL back when she first joined the X-men. Witness her to suggestion to Storm that the best way to deal w/ Havok &/or protect him was to "KILL HIM!" , also when she had a rematch w/ Sabretooth during the Inferno & she KILLED him w/ a vicious telepathic attack. Rogue & Wolverine confirmed his death but of course that was retconned later on when he resurfaced sometime later.
Psylocke was also @ one point one of Storm's advisors/ deputy leaders, alongside Wolverine during Claremont's reign over the X-men. When Storm seemingly died following the battle w/ Nanny & Orphanmaker & Wolverine was missing in action & all that were let were Dazzler, Havok, Colossus & Psylocke, Psylocke effectively took over leadership.
Havok @ one point even said "you talk like YOU'RE boss now" & Psylocke replied, "Find me someone better & I shall step aside."
Psylocke has prooven to be a trusted advisor, counselor & leader. But these days ppl prefer to writer her as psychic/ninja muscle rather than the intelligent person she was once presented as. I also dont agree w/ them saying she "can be developed to be as powerful as Emma..." Psylocke has prooven MANY a time to be a top tier telepath & was regarded as such by Storm, Wolverine, The Hand, Mandarin, Mr. Sinister & even Cyclops. She was considered to be more ruthless than Xavier w/ her powers & many ppl, including her friends were scared of her. Writers dumbed her down to make Jean look stronger b/c for the longest time it was obvious that Jean was NO MATCH for Psylocke.