In the Matrix, Morpheus guesses that the true Earth year is around 2300, rather than the simulation setting of 1999. However, Morpheus is unaware of the number of iterations the Matrix has undergone.

At the very least, there are the first few iterations in which the Matrix experiences system-wide crashes due to humans being unable to accept the program created by the Architect.

Then, the Architect mitigates the problem with various controls and the institution of choice among the humans, conscious or otherwise. In this mitigation, "The One" arises and is used to update the program and the system is reset with the new program. The Architect reveals that there are six such emergences.

In addition, there were earlier iterations marked by systemic crashes where "The One" did not emerge.

If you include all these different iterations -- the first two, the 6 where The One emerges, and some undetermined number of ones where The One does not, there would probably be at least nine, but you could be imagining 10, 20, or even more.

Considering the possible spans of time involved in the initiation of an iteration to its reset or collapse, maybe you're looking at 50 to 100s of years.

So, I suppose the actual Earth age would be in the realm of thousands of years beyond the 1999 Matrix setting, rather than merely 300. Maybe the true year could conceivably be 3000 or 4000, or more.