I use this liberally. Generally, it is a runtime performance issue only on repeated allocations for which you can optimize if needed. Once-only allocations can be ignored when using compiler firewalls.
Generally, I find when people crow about performance, the product they're talking about usually has some questionable architectural/design/implentation decisions that dominate the performance issues so I have to do my best not to roll my eyes.
Yes, you can write performant C++ using well-understood compiler firewalls, interfaces, etc that reduce your compile time.
Well, this is "Hacker News" and not "Groklaw". There needs to be some recourse to the public accusation. If I was him, I would have just "noped" my way out of it.