That's not the argument he was getting at.
Tower law generally prevents the Aes Sedai from abusing their power. It doesn't explain why so many of them are just bad / inefficient / behind the curve at using it.
Like, compare the Aes Sedai to the Wise Ones or the Windfinders. Windfinders could do stuff with weather / wind manipulation that made the best Aes Sedai in the tower look like kids stumbling around in the dark. Wise Ones were chucking fireballs at shit they couldn't even see / stuff behind them, which tower trained Aes Sedai would have considered almost impossible to do. As the series moves on, it becomes very obvious that the White Tower has basically stifled innovation and experimentation when it comes to One Power use, and quite possibly has set the Aes Sedai as an orginization back centuries in terms of actually using the power to it's full potential.
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I kind of understand why they basically deleted Thom from the TV series, mainly because Thom's the kind of character that is almost impossible to get right in Live Action. You would need a world class actor to pull Thom off properly. Bout the only person who I could think of that might have been able to do it would have been Sean Connery in his 50's.
Thom is a Grand Master level performance artist. He's a master of disguise, capable of changing not only his appearance but his mannerisms and character to the point where he can basically become an almost completely different person. He's hobnobbed in literally every social circle from being Personal Bard to Kings to Gleeman playing taverns for dinner money. He's probably forgotten more about political intrigue and geopolitics than most people learn in a lifetime. The guy just straight up oozes charm, whit and charisma, but is also capable of picking up practically any musical instrument and straight up captivating an audience as if they were under a spell.
I honestly don't think the TV series could do any attempt at getting "Thom Plays an Instrument for a Crowd" right, no matter how hard they tried.