Reality

About 390,000 kids in foster care

Of those, about 65,000 are eligible for adoption

But about half of those are already in process of being adopted.

The actual number eligible is around 30,000 or less.

The 100,000 figured comes from a misreading of a published data point that measured “a goal of adoption”, but not actually eligible for adoption.

No one in the comment thread question the 100k claim.