No, no... that's plain wrong. There are quantifiable factors that shall be taken into account when making such decision, and I'm sure more than ever that GitLab is more suitable for businesses and projects using multiple repositories in general.

In GitLab you can have organization wide policies and settings, you can group people and repositories and their CI/CD doesn't depend on complex scripts written in JavaScript that come from public market place and cannot be used by most companies for security reasons (no tampering guarantee with actions on GitHub). GitLab MR workflow with threads in discussions and per file reviews and dedicated reviewers is superior to GitHub and much more suitable for commercial setting. There are tools that allow to run GitLab's CI locally on the workstation, what may make DevOps work easier.

GitHub was designed to host open-source projects in the first place and to this day pays price of some early decisions, which can be quite painful for larger organisations, like lack of organisation wide settings of many factors (backlinks to ticket management is just one example, access control to repositories is another). On GitHub structure of repositories is flat, not groups. CI system relies on scripts written in JavaScript pulled from marketplace w/o guarantee about tampering with them, so they may steal you code from private repositories if changes made by rouge parties. GH improved their PR reviews over last 2 years, but it's still not close to what GitLab or BitBucket has to offer in that regard. If you need merge queueing that works, you need third party tools, while GitLab has merge trains built-in (yes, premium service, but businesses usually pay subscriptions).

My advice is: if you're serious software startup, don't hesitate and go for GitLab (you'd thank me later); if you're planning only to build open-source or host some tools without external ticketing, GitHub shall be your choice as easier to use for such cases. Keep in mind your decision is going to be set in store as any migration while not impossible, would cost you dear.