...does he mean "Top Five Recruits" nationally? Or in ND's list? And, of course, which Class?

I'll guess the reference is to Top Five nationally and use Hoopgurlz as the barometer.

2020: Caitlin Clark (that's a process of elimination: Bueckers and Brink have committed and we're not on Reese's finalist list).
This would be very optimal!

2021: Point Guard Olivia Miles or Post Amari DeBerry.
Can't see Azzi Fudd, in the process of some kind of rehabilitation, coming out to a campus she's been to a few times. Miles and DeBerry just finished the tour of duty with the U.S. National Team and AAU tourneys don't pick up until after the holidays, so this would be a good time.

Prospects Nation has Clark at #7.

Prospects Nation has Fudd, Deberry and Miles at #1, 2 and 3.

Some recruits don't want to be hounded by every recruiting service and the media outlets that cover the top programs.

Some don't want to keep answering the same questions over and over again. How was your visit? Which schools are on your list? Is there a leader? Who contacts you most often? When will you narrow your list? When do you plan to commit?

The last original recruiting question was asked in a prior millenium. Taking calls and politely responding must get old; but don't take calls or get short with the questions and you're a prima donna. I can see why one might want to stay under the radar.

Also, Michigan sucks.

in the near future would most likely do it secretly if she doesn’t want all the hoopla of freinds, fans, and media nagging her about where she might go. Caitlin seems very private as well.
On the other hand, why would a 2021 or beyond recruit care about doing a secret visit, her decision is probably at least a year away, but I guess anything is possible

Someone like Deberry. But I suppose Clark could have had a bad experience with the aftermath of her Oregon visit.

I hope it was her & she had a wonderful visit and will commit to the Irish down the road