the connotations you see in the example are inherent to the word; viz:

one that has risen (as by the acquisition of wealth or power) above the station in life in which he was born; especially : one that is unaccustomed to his new station or that makes great pretensions because of his acquired wealth : UPSTART [W3 - emphasis added]

Usu. derogatory.
A. n.
A person from a humble background who has rapidly gained wealth or an influential social position; a nouveau riche; an upstart, a social climber. Also in extended use.
Generally used with the implication that the person concerned is unsuited to the new social position, esp. through lacking the necessary manners or accomplishments. [OED3]