Just to give you some background information:
In comparison, Japanese sales figures for the original Door to Phantomile on the PS1 sold 51,441 units in its first week and went on to sell 159,284 units. The original JP release of Lunatea's Veil on the PS2 sold 45,639 units in its first week and 133,401 units in nine months.
https://old.reddit.com/r/Klonoa/comments/xc3b9l/klonoa_phantasy_reverie_series_total_sales/
This one is giving you 25851 sales in north america:
So there were never that much copies out there and there can't be that many copys left. The game was released 27 years ago - discs were thrown out, were destroyed, became scratched and unreadable, house fires, floods etc. happened, but even if every copy was still in existence: You would still only need 25852 people who are trying to collect all north american PSX releases to create a scarity.