> If quacks like a dick, it is a duck.
I assume there is a misspelling one place or another there, but, yes, much of that introductory paragraph was pointing out that fairly canonically Starfleet (or, extracanonically, Star Trek's creators) are in deep denial about the nature of Starfleet.
> Kithomer Accords, re-established between Cpt. Sisko and Chancellor Gowron, the first accords were Picard's job (could be wrong about that)
The First Khitomer Accords were negotiated between the civilian leadership of the Federation and the Klingon Empire in the wake of the disaster created by the explosion of Praxis; there was a conspiracy involving the highest levels of both Starfleet (led by Admiral Cartwright, the CinC Starfleet) and the Klingon military (led by General Chang [0]) to sabotage the negotiations, foiled by (among others) the crew of the about-to-be-decommissioned USS Enterprise-A under Captain Kirk, after he was rescued by his crew from his imprisonment on Rura Penthe, having been framed by the conspirators for the murder of the Klingon Chancellor Gorkon, who the Enterprise was to be escorting to the negotiations originally planned to be on Earth, which were secretly rescheduled and moved to Khitomer after Gorkon's assassination. (Star Trek VI: The Undiscovered Country)
> everything Bajor related, despite the planet being the most strategic important one in the Alpha Quadrant there was never an official embassy mentioned, everything was run by Sisko
Sisko's adoption by the Bajoran religion as the Emissary of the Prophets was frequently referred to as an issue with forced Starfleet and the Federation more broadly to deal with Bajor other than the way they would prefer to.
> - the ultimate peace treaty between the Dominion and the Federation
The Treaty of Bajor was very much setup (while the substantive content was not at all similar) to be an analog of the Japanese Instrument of Surrender, signed for the US by Gen. MacArthur. (To the point of Admiral Ross directly quoting MacArthur.)
> Just from top of my head, all major diplomatic treaties have been negotiated by Starfleet personell.
Clearly not, aside from the Khitomer accords, just a couple examples of many: In "Journey to Babel" (TOS), the Enterprise is transporting ambassadors from several Federation worlds to a conference on the admission of Coridian to the federation; the Treaty of Alliance between the Klingons and the Federation had Ambassador Sarek of Vulcan as the lead Federation diplomat, referenced in "Sarek" (TNG), etc.
[0] A clearly senior military officer described by Chancellor Gorkon as "my chief of staff", but I don't think its clear whether he was the Chancellor's CoS in a sense analogous to the White House Chief of Staff to a US President or whether his role was as a military CoS, or whether the distinction between the roles is foreign to the Klingon system of the time.