It may help to reframe the situation a little. Let's establish a baseline first. In order for us to provide support for a game or service, that game or service needs to generate enough ongoing money to pay for all costs associated with the continued support plus a reasonable profit. We're looking for sustainability - players keep giving us enough money that we can afford to continue making more of the game. That sounds reasonable, right?
We enter this with some general expectations - some percentage of players will convert to spending additional money on things like microtransactions, battle passes, season passes, cosmetics, story DLC, additional characters, loot boxes, whatever. Some percentage of players will never spend a penny beyond the initial buy-in for the game. These percentages are factors of the total player base - only players who bought the game will spend money on DLC/microtransactions/etc. Generally, this means we need a certain number of sales + a certain percentage of those players to pay for additional content in order to pay for any continued game development.
If we don't get enough sales, we most likely won't ever have enough paying players to financially justify continued game development. This is what happened most recently with Immortals of Aveum - they missed their sales goal by a significant amount, so they laid off half the studio and cancelled all plans for ongoing content development.
If we do get enough sales (or close to enough) but don't get enough paying players among the overall players, we won't have enough revenue to justify continued game development. What may end up happening in this situation is that the publisher gives the dev studio a chance to save themselves by coming up with some way to get to sustainability. Bioware's Anthem falls under this category.
It isn't really sales that matter though - engagement (time spent playing the game regularly) is the real metric that everybody is paying attention to, because it is the metric most closely correlated to players being willing to spend money on a game. If you've got a highly engaging game with lots of players playing it every day, it will almost certainly get more support. If engagement falls, players will churn out and the money will dry up, which leads to the game getting sunset.
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