Full details here. In a nut shell:
No MQMs or MQMs will be used for status earn, MQD only
Status earn only through Delta flight purchase, Delta vacation/car rentals, or Delta AMEX card spend
1 x MQD for every $10 spent in Delta AMEX Reserve
1 x MQD for every $20 spent for Platinum
10 lounge visits per year for delta AMEX reserve starting in 2025
6 lounge visits per year for Platinum starting in 2025
No lounge visits for Platinum in 2024
These are huge changes that are going to hurt medallion members who make their status on the fringes. I know United raised their bar for status qualification this year so I wonder if this is response to that and/or the want to make their medallion statuses more elite again. During pandemic they made a lot of exceptions and relaxing of rules to keep their customer base while air travel was low and as a result, I was able to keep my platinum status for 3 years in a row with minimal traveling. I'm presuming many others were as well which likely leads to lounge overcrowding and high competition for upgrades.
Part of me wonders if there will be some whiplash effect as a result from cardholders. To only earn 1 MQD for every $10 spent on a card that has a $550 annual fee is pretty egregious. Additionally, Delta has been typically at the top of the list for best rewards programs (usually behind Alaska) so I wonder how that will shake out as well. I personally think Delta feels it has earned enough of a reputation as an "elite" airline that it can sell an elite experience at a higher cost.