The only argument that seems to be made for keeping the old adventures is that retiring them would 'take away options'. I don't see that three full seasons of AL outside of Season One, plus three hardcovers outside the two Season One hardcover adventures, plus convention content, plus Lost Mine adds up to 'not enough content'. As such the real argument seems to be that people would feel bad if they couldn't play certain adventures for AL rewards. While I understand that AL isn't in the business of making players feel bad, the reality is that the admins and authors do spend significant time developing narrative storylines, both within seasons and foreshadowed for future seasons, and while people may not care about them, the AL does use them in how it runs the campaign.
Pauper
And since no rational arguments have been made for retiring old adventures, that looks like a win for keeping them. Since it seems likely that the adventures will continue to be available, I guess that you will just have to continue to rail against people having fun that you don't approve of.