A productive day: laundry, kitchen-work, helping a relative with computer software and hardware issues, shopping errands, government-required paperwork...it's been a good Saturday.
Someone on Facebook suggested the moment that began that decline was when Benjamin Sisko decided to run with Elim Garak's ideas per "In the Pale Moonlight" on DS9 during the Dominion War.
I think it was about a decade earlier: "Q Who", where Q introduced the Federation and the Borg to each other.