I called it as I see it.Actually Constituion-class is indeed referenced in TOS only rather subtly. In two instances schematics are flashed onto a view screen that reference Constituion-class. One is of a phaser schematic viewed by Khan in “Space Seed” and the other is of ships shown on the briefing room view screen in “The Enterprisr Incident.”
But TOS never referenced that the Enterprise was the last surviving Connie. That is retconned from GR’s novelization of TMP.
A series of fanfilms claiming to pay homage to TOS felt compelled to honor whatever was done after the series was cancelled. After Star Trek, it seemed GR was drinking the kool-aid of being this great bird of the galaxy, probably started from the Trek-conventions, and started thinking he was some kind of visionary.
Having these ships be obliterated in STC so easily don't honor how durable and special these Star Ships were. Sad to think "A Mirror Darkly pt. II" and "The Tressaurian Intersection" were only creative pieces who got it right. These Starship Class vessels were something to behold.