All true, but none of this is new, and has been the case for years. Thing is though these £60 games will sell out except for some exchange tickets. The games that don't are the cheaper £40 games, so while I agree with you would reducing the price to £30 sell many more tickets for the £40 games?
A season ticket will always be cheaper if you are going to more than half the games, which is the cause of the majority of empty seats, because s/c holders can afford to miss a few games and still save money on matchday, so I'd make s/c a bit dearer,which will cause an outcry, and make matchday tickets cheaper, or my preference introduce a scheme where you get discount the more matchday tickets you buy.