Exactly. I respect their decision to go closed source if that's what they need to do to make it a viable business, but just be honest about it. Don't make up some excuse around security and open source.
Now it's a lot easier to rewrite open source stuff to get around licensing requirements and have an LLM watch the repo and copy all improvements and fixes, so the bar for a competitor to come along and get 10 years of work for free it a lot lower.
The issue is competitors popping up to clone your offering with your own codebase.