The most equivalent milestone to MVP in games is first playable (FP) or prototype. This is done at first pass/L1/greybox quality.
Vertical slice (VS) is a type of beautiful corner — this is done at production quality.
The purpose of FP is to prove the game loop and that a game is worth producing — that it is viable, or you could say that it has reached the minimum viable state. The purpose of VS is to try out the entire production process and test burndowns, etc.
I can confirm, as someone who has worked in games for decades, that the author understands it correctly.
FP in automotive would be a prototype car, VS in automotive would be the first factory produced car. VS in games often marks the end of pre-production and a shift of priorities from iterating and experimenting to producing bulk content. MVP would be much earlier.
Then in another sense, MVP is already marketable and commercially viable. But a game is that neither at VS nor FP. So if you look at MVP from that perspective, it is not even close to either VS or FP. It would be like somewhere beyond around alpha. In any case, MVP != VS :)
The MVP concept doesn’t work with game production that well because it’s a hit driven industry where most of the costs go into producing the hit. Like in movies, music, TV and book publishing — there are many stages of green-lighting before a product is first made available to the market as going from zero to market is where the bulk of the costs are. Going zero to market MVP as the first green-light check would be quite expensive ($50M for market leading VR/handheld, $100M for market leading console and Windows games minimum spent by the time a game is shown to the players) and risky. So instead, we start green-lighting and reviewing the prototype when <$2M is spent in most cases.