"The average person" is a pretty meaningless term. A lot of people will never have access to $4000 worth of savings that they can put into BTC all at once.
I'm not interested in owning micro or milli coins.
Why not? People should buy as much as they're willing to spend in fiat. The BTC price at the time is irrelevant to how much you're prepared to buy.
Can someone tell me where we are on this chart please?
Depends how you're defining BTC. As the original vision, a "digital cash system", we're still in the innovator phase, since the vast majority of merchants don't accept BTC and those that do still only have a small amount of their purchases in it.
If you're defining it as a store of value, then probably still in the innovator phase but perhaps bordering on the early adopter phase.
The mistake that people make is thinking that a high market cap is a high number of "ordinary" people investing "ordinary" amounts. The reality is that there are still whales who hold huge amounts of coins because they bought in earlier, so it's hard to say even roughly how many users there are.