If it's anything like [the last strike] in 2016, it will likely follow the same procedure. If the union chooses to strike, any games that started development before a certain cutoff date would continue unaffected. Any games that start development after that cutoff date will be struck until an agreement is reached.
To my recollection, only about 40% of video game voice acting is done by union workers anyway. Indie studios and smaller publishers don't really have the money to pay union scale and often save money by using their developers or friends/family as actors. Hades, for example, had a large number of non-union voice actors. This is mostly setting up an agreement for large AAA games. Union actors will also sometimes do non-union work under an alias (like Cam Clarke being credited as "James Flinders" in Metal Gear Solid) to dodge the union rules, and that would likely continue.
Generally speaking, the amount of negotiating power the actors have with game publishers is significantly lower than when negotiating with the MPAA. Voice acting does matter and can elevate certain kinds of games (mostly narrative- or character-driven games like Baldur's Gate 3 or Mortal Kombat 1), but it certainly isn't universal - people don't play Minecraft, Counter-Strike, or Pokemon for the vocal performances. I wish the union luck in their negotiations and I hope that everybody reaches a mutually beneficial agreement. My main sympathies remain with the non-union voice actors out there who get the squeeze - joining the union is quite expensive and difficult, and the union obviously prioritizes union work over non-union members.
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