There is a trend in the film industry of not showing pre-screenings of upcoming movies when the studio doesn't believe the film is that good. This is an attempt to avoid people reading negative reviews and to get uncertain people into seats before they hear anything. I'm not sure if that really works or not, but some games publishers have been utilizing similar practices in recent years. Bethesda is the most prominent, outright refusing to send review codes until the day of release, but it looks like Sega is now following suit with Sonic Forces.
Ever since its initial reveal trailer, fans have been speculative of the quality of Forces. Shown alongside the 2D revival Sonic Mania, it looked like the proper Sonic Team game was going to get upstaged by a fan project. While we still don't know if that is true, this pre-release embargo might as well outright confirm it. Why else would Sega not want reviewers to play the game early?
This news was confirmed by IGN's executive editor of reviews, Dan Stapleton, on twitter.
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