Concerning OP I don’t think direct CCP intervention is necessary, as in PLEX sales, etc.
But there are ways CCP can influence this matter indirectly.
If there is mineral overproduction, and I think there is, you need to make professions that are attractive to your miner community, so that they feel incentive to switch from mining themselves. They keep using their ships and skills, but are not producing excess minerals. Something RW could do BTW, if rewards were right.
I cant think of a way to do that to bounty and SP farmers. I’m not accusing them RMT, but we know many of them do bot and RMT.
Take any useful deadspace module. It costs twice its price 5 years ago. Is it because higher demand? There are still the same number of players on average. Abyss? Yes, it clearly did influence. But much more players do combat exploration than 5 years ago, so supply is there to drive price down. Yet it doesn’t. ISK got cheaper. Twice cheaper if not more.