Yeah I called BS when I read that line too. I pay for plenty of dev tools. Similar list to you.
* JetBrains (PyCharm professional, DataGrip, and Goland) ~$250/yr
* Lucidchart (Diagramming) ~100 /yr
* Paw (HTTP Client) ~$50 /yr
* Docker Pro ~$60 /yr
I think there's probably more, but I'm not at my work laptop to look, but those are the big ones. Those are only individual subscriptions. There's also huge costs when associated with things like Gitlab Premium ($20 - $100 /user/month), CI/CD, Code coverage tools, security scanners, etc. Companies pay A LOT for development tools.
If Kite thinks that the problem why no one will pay $9/mo for their service is because developers or their company's are cheap, they need to re-assess. The reason they couldn't sell their service is because it wasn't providing enough value to justify it. But companies are paying hundreds of dollars a month per developer in most cases for various tools. The extra $9 for Kite isn't the dealbreaker if there was enough value from it.