Originally Posted by xliioper

No access for regular Amex Plat cardholders when flying DL partners with exception of DL marketed/WS flights -- https://www.delta.com/us/en/delta-sky-club/access

If you had Gold or higher Delta status, you get access by virtue of VS/DL relationship (suspect this would likely cover many Amex Plat cardholders who also happen to fly DL regularly).

For larger stations, there would generally be a Priority Pass Select lounge covered by PP membership from Amex Plat. But that is not the case for TPA.