Who is saying this? I think even Calle said ecash doesn't scale bitcoin. It does add privacy to custodial solutions. 

 Yes, Calle is extremely clear that ecash doesn't actually scale Bitcoin, but somehow there are many who still think and say so 

 Not true. The anonymous credentials created in WabiSabi coinjoins can be used as a second layer: https://twitter.com/MrKukks/status/1619294643451199489 

 Sounds interesting I need to look more into this, but even if this offers anonymity, Wasabi Coinjoins are not ecash so don't offer the same level of privacy 

 Does this actually scale non-custodial and permissionlessly? 

 Hope you're pro covenants, otherwise custodial bitcoin is the only real way.