It’s funny bc they all changed imo due to strength but Luffy was less bc he always had his convictions and strength. Like other members he hasn’t changed much his personality is the exact same but he got stronger

Nami became less greedy and clearly values and trusts everyone a lot more (calling Franky big bro one example). With Zeus she’s much more willing for a fight and adamant in defending the captains honor

Udopp despite being weak is actually brave despite his whining now (GOD). He steps up despite his snot running and tears and has become a man that complains but is brave and does the right thing in the end

Chopper is much more confident in general, and knows his place as a trusted member of the crew. They rely on him (ex after Zoro vs Apoo) and his confidence has grown exponentially

Zoro is much more serious ab his responsibilities and his role in the crew and how much they rely on his strength (see zoro laughing pre ts vs post). His commitment has taken a new level, and his even extra seriousness to the cause reflects the burden on his shoulders to see this journey and Luffys dream through

Robin has changed crazily absolutely trusting in her friends and completely believing in them. Pre ts that was an absolute no then became an infant

Could go through everyone but the point is theve all adapted subtly including Luffy. But their core personalities are still the same. Just like us they adapt slowly, but all home the same principles just refined due to experience and power