The cons is that Google can break the endpoint at any time.
That said, I wrote a similar hack for a Wordpress plugin 10 years ago which automatically generated articles in multiple languages (think SEO farming).
I just looked at what their frontend app was calling and used it.
I run a business which needs to run programmatically searches on different search engines and using official APIs is out of the question. I didn't even check what their API offering is.
The only search engine that seriously try to prevents scraper is Yandex which asks for a lot of captchas but I've built a system to allow humans to just process captchas and give back to the code the result.