While "Socialist" has a relatively specific meaning, "progressive" has a much wider variety of similar meanings, which definitely include the usage I indicated,

While "Socialist" has a relatively specific meaning, "progressive" has a much wider variety of similar meanings, which definitely include the usage I indicated, without any need for recourse to the related word "progress". Attempting to now restrict the word "progressive" to just one of its meanings in a politically biased way reeks of newspeak style attempts to control what people can express.