Morphy was a great player, but his games were played during an era characterized by flashy tactics (the era of Romantic chess).
Steinitz developed a new "positional" chess that was more principled and solid, with strategical maneuvering, study of pawn structure, etc. Thus these more modern games are better for study.
See here for more information about the different schools of chess.
But what about tal, Shirov, Stein,Speilman. DIdnt these guys play alot like morphy (in an attacking sense?). Even Fischer enjoyed studying Morphys games and yes before the 21st game of the 72 match with Spassky he even studied Anderssens games. So i dont really get it. Does modern chess study nowadays stay away from Morphys approach? Is there something wrong with Morphys chess style that is not applicable to modern times?
Kinda find it wierd though, but i was in a group discussion in the chess park near my home and players where expressing the idea that even the Russians then, started studying chess from Steintz to ALekhine games. So whats wrong with that of Morphy why not study them? Are morphy's games irrelevant in getting better and studying chess?