for those who have a good SET to play in the "Modern Format" it is much better to focus all their resources in playing there than in the "Wild"

The company has this view all wrong. Modern format is the competitive, higher-earning format. It should be where the more competitive players want to go for higher prizes and the human environment. It should encourage the most active players to get cards from the newest set to compete at the highest level.

This keeps the game going. This funds the DAO. This funds the company to develop the next set. It provides for SPS rewards past the print run that ends in 2 years that nobody seems to want to talk about or plan for.

Wild should be the more casual format for most players and bots. There is still a place for the most competitive players with all the cards in the history of the game. But the truth that Matt has brought up before that there needs to be some limit on the incentives given to the wild format where people can just earn rewards indefinitely with a modest amount of newer/cheaper cards only.

The biggest incentive for older cards is TOURNAMENTS, because I just don't care about lands at all. But the top-tier events demand owning (or renting) the best cards in the metagame to ensure success. This will always prop up card value and rental value because of the expected value of ranked and tournament winnings.

So I respectfully disagree with your premise about wild. It should be the casual format where people can earn forever with their older cards. Modern should be competitive with bigger prizes with the newest cards. The best cards, old or not, will always benefit for higher price tags with shorter print runs due to supply and demand.

Now with the new pack sale mechanism and battle wagons, the game will finally have the right amount of cards for its players. Prices should be more steady for the newer cards, even past rotation. It does not solve the problem of propping up the value of the older cards, but only the most useful for the most competitive battlemage will retain their price long-term.