He is 100% right - even in my younger days where I was a lot more woke and my peers were talking about no platforming people i always argued for free speech.
The only way to defeat those extremists is to debate their arguments and find the flaws in their ideologies. Look at Nick Griffin as a prime example, I remember arguing with my friends with them saying he shouldn't be allowed on QT and I was for it as his arguments wouldn't hold up. That performance ruined his career yet people still think that you shouldn't ever give a platform to these people. Give them the mic and tear them down, show them for what they are.
This is why TRAs won't debate as their ideas won't hold up. Cowardly behaviour.