How many international judo competitors throw ambidextrously?

From the Judo Chop Suey Podcast, Episode 26: Interview with Christopher Round at ~49:18, the interviewee Christopher Round, a former US Olympic hopeful, addresses this point while discussing where he reached his competitive ceiling:

I started running into players who were ambidextrous. And it's very rare for a player to be very good who is ambidextrous...[indistinct]. A lot of high level players, they'll have attacks that are both sided, but to be a true ambidextrous player, I can count on one hand the number of people I knew who did that at a world level. Won Hee Lee was an example of someone who could do that. Won Hee Lee for those that don't remember him, he was a very, very good player from South Korea. He won the world championships in '03. He was a guy who beat Jimmy [Pedro] in the third round of Athens [Olympics]. And I actually, my brain would just like, malfunction when I would handle those players. I was used to very disciplined judo players. And I realized, and once some of the people I fought realized that if they kept throwing different looks at me, I would have trouble keeping track. I started running into stuff that people could do that I just kinda couldn't keep up with. And that's not to say that I couldn't keep up with, to a large extent, a lot of very good judo players.

It appears very few players are ambidextrous, but being ambidextrous is an advantage.