It is hardly even a round enough number to matter....
My speculation is that probably 25k and 30k will be more significant.
You do realize that 21 has a very special meaning for bitcoiners, right? However, it may take us a while to reach 21 million pages.
If you put it like that, then o.k.... I do understand that.
On the other hand, I did recognize 10k and 20k and 50k, and 100k..... .. ... Probably price/page parity is going to come well before 50k, and likely before 30k.. and perhaps, when BTC price goes over page parity this next time, it will largely stay over it.... (but I would not be surprised with a few more dips below page count.... It was nice to have a bit of price above page count in the mid-$19,000s, but it did not last for very long.. that's for sure.... a few days, maybe? Recall that?