I'm not sure if it's really company size, though there's probably a correlation. My company is only marginally bigger than GitLab in terms of employees (just recently 200+), and we have several dozen databases bigger than this.
This, it depends more on the product and the requirements. I've worked in companies that are just a few employees and are running databases larger than this. I've also worked for a company with ~100 employees whose only 'database' is an in memory cache and a few kilobytes big textfile