You see this in tons of domains, not just chess. My personal hypothesis is that it has become so much easier to study and improve yourself based on the past insights of others, and this network creates ever accelerating standards.

For example, I recently (as a middle aged adult) took up ice skating. It probably won't be too long before I'll be at "early 1900s Olympic champion" level. Reason being that those early Olympic champions basically had to figure out how to do everything by trial and error. These days I can watch countless videos on YouTube explaining exactly how to practice certain elements.

So yes, the inequality factor is certainly there, but with even homeless people getting access to a base level smartphone these days I don't necessarily think it's insurmountable.