3. Technology is Stagnant
There are plenty of signs of a dying civilization: decline in military strength, loss of economic independence, reality television. However, the most certain measure of a culture is their technological progression. The Elder Scrolls games span 240 years of history in Tamriel, but what happens in those 240 years? Well the world almost ends a couple of times. There are a few wars to keep people's mind off of the next apocalyptic event. That's kind of it. No great inventors or discoveries. No major technological advances. Nothing truly valuable or helpful for society. Most societies advance in technological bursts, followed by slow steady gains. Cultures discover things like agriculture or the microchip, which results in a massive jump in technological achievement. However, in Tamriel there doesn't seem to have been any technological advances since the discovery of steel. In fact, the residents of Tamriel seem to be stuck in a technological regression, resulting in an extended dark age; one started by the disappearance of the Dwemer. And there you have it. The thousand years of technological stagnation is likely the result of a bunch of cave dwelling, elf enslaving little people deciding that they wanted to
pull a Harry Houdini with their entire society. In case you're not up to date on your history of Tamriel (for shame), the Dwemer had everything from steam power to mechanical locks and high powered telescopes. One day they decided to lock all the doors to their culture and disappear completely. Apparently, without the Dwemer to think of everything, the rest of the world conceded that only dwarves can invent stuff, and consigned the rest of existence to farming dirt and fighting with swords. And all this all happened about 1000 Years in the past, leaving us to assume that the people of Tamriel have not and will not become interested in technological advancement. So, they will still be hacking at each other with axes when someone with tanks and machine guns lands on their shore with ill intent. Lightning axes may be very effective against bears and trolls, but something tells me they wouldn't be all that effective against a culture that has developed bomber airplanes.