Reddit user leakingtruth claims that American Express is making changes to Delta lounge access:
Prolly not exciting news, but there is a huge change coming to Amex delta cards and Plat cards in terms of lounge access.
Delta will be restricting access to Delta Plat cards, and Delta Reserve cards will still have access but greatly restricted starting on 2024-2025. Platinum card holders will also be restricted from Delta Skyclubs and will have only up to 6 complimentary access per year
Post history seems to indicate they work for American Express, but it’s always difficult to know how reliable this sort of information is. We’ve reached out to other contacts but have yet been able to confirm these details.
Source: doctorofcredit.com