In the video game industry, AAA (Triple-A) is a buzzword used to classify video games produced or distributed by a mid-sized or major publisher, which typically have higher development and marketing budgets than other tiers of games.
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The term “AAA” began to be used in the late 1990s by game retailers attempting to gauge interest in upcoming titles, and first appeared in print in a press release from Infogrames in June 2000. The term was likely borrowed from the credit industry’s bond ratings, where “AAA” bonds represent the safest investment opportunity and are the most likely to meet their financial goals.

https://en.wikipedia.org/wiki/AAA_(video_game_industryDLC

Since then it has become shorthand for large budget games produced for major publishers and the problems that come with that:

• “safe” game design and themes that a major business might require before they invest 100s of million dollars on the project. This will often means that they follow industry wide trends (e.g. zombies, or open world game with crafting)
• overpriced for the base games, special editions, and often season pass and DLCs. again its the business trying to make good a profit on their investment
• if the design allows it be padded with copy-paste content to increase game time in an effort to justify the high price. (see: Ubisoft syndrome).