its just as simple as when it was 100k ppl had less money now ppl have more money so values go higher too, people have milions now, its not that hard to make money, so it wouldn't be fair for people who spend their irl money to keep the price 100k when ppl got milions lol
but i would agree that the value of ms shouldnt go higher than 300-400k because ms doesnt give much, only access to some poks which eventually will be catchable in other places too, ms in other games used to be with milions because it raises the shiny encounter rate, in this game it shouldnt be a lot :p