I'm not sure "the startup is disappearing" is the only explanation for this data. Isn't it possible that companies are just lasting longer than 2 years?

What if there was a larger percentage of age 0-2 companies '85 because back then, so few were making it past 2? Maybe easier access to capital has increased survival rate (or at least slowed down dissolution by a few years).

This explanation also fits better with the massive influx of cash into VC over the last ~10 years.