I have spoken to many too actually. Just as you have. In La La Land.
Usually when people find it impossible to believe that connections and direct reliable information to the CNT or other top players exist, it's a sign that they are complete casuals who have zero connection to or experience in the pro landscape. But surely you aren't one of these people.
In your case, since you know so much about the CNT and CNT-related matters and people, perhaps you can fill me in on who these people are, if they are directly connected to CNT players and coaches, what they have in common, and whether they are people actively involved in the USA (see my flair) scene or if they are mythical and untouchable beings. This is just a very short list to keep things brief.
Gao Jun - I'll give you a hint on this one. Close friend of and highly respected by Liu Guoliang, as well as top players on the CNT. CNT players stand at attention and pay the utmost respect when she enters the room and speaks and she is the main reason there have been so many CNT and USANT ping pong diplomacy events, collaborations (such as mixed doubles at the 2021 Houston WTTC) and closed trainings / pre-tournament training sessions.
Tao Wenzhang
Zhou Xin
Kou Lei
Jinbao Ma
Wang Wei
Wang Hui
Bob Chen
Jishan Liang
Lily Zhang
Xiangjing Zhang
Your logic from your "discussions" is to assume that all players must have been cloning someone on the come up, even a youngster already being prepared for the big stage as early as 16,17 are clones because of their playing hand. That's quite flawless logic I must say. Aristotle is turning in his grave in awe at the marvel you just synthesized.
They are not groomed to be "clones" from an early age. Rather they are selected and given opportunities to train with the CNT once they reach a high enough level and if they have an in-demand characteristic that meets a certain need that the team wants. You should know this as someone who is clearly very in tune with what goes on with the CNT so why would you suggest that?
Funny thing is the Chinese themselves do not have as many practice partners to choose from anyway
Oh really? Then why do they bring an entourage several times the size of any other national team's to all the major tournaments and most of the mid tier ones as well? Why do they bring such a big team that oftentimes there is a CNT-only hotel and then another one where everyone else has to stay? For every training partner, physio, coach, admin staff that players from other countries have, Chinese team will often have maybe 2-5x more. Anyone who has actually been behind the scenes maybe such as
@Tony's Table Tennis knows this, I'm surprised you don't?