I've never heard of "free to enter" in the context of gaming. It's well understood at F2P or FtP (
https://en.wikipedia.org/wiki/Free-to-play)
I think it's possible that they chose those words for SEO/web crawling reasons as they don't want to be associated with F2P or the HR person who helped draft the job description wrote it that way and it was never changed
But maybe they specifically say Free to Enter in order to differentiate from games like Fornite, which are really free to play but rely on microtransactions for revenue. Free to Enter could suggest a very minimal base game with large DLC EPs being almost required to do anything.
