I think it's worth pointing out that german is a language where every noun has a gender. "Spieler" (player) is male. If you wanted the Guilds rulebook to use the female form, you couldn't just replace "she" with "sie". To be grammatically consistent, you'd be forced to also replace the word "player" with something else. As i pointed out before with Baker, "Spielerin" feels like it intentionally excludes male players, while "Spieler" includes everyone. You can argue why female has to be a special, more restrictive variant of the male version, and i agree it's an issue, but it's an issue that has grown historically and has been mixed with grammar, making it part of the language itself. This still doesn't mean Altenburger couldn't have used Spielerin, but it would have taken a bit more from them than just "stick to the original".
On the other side, take the word "Person"(person, obviously), which is grammatically female in german. "Ich bin eine Person" can be said by people of either gender with no issue at all. Using it to translate the word player, the entire rulebook could have been grammatically consistent using the female pronoun exclusively, and i personally don't think it would have been noticeable even. The only problem is that "person" sounds a bit remote and doesn't mean quite the same as "player". Still, it's a solution i'll keep in mind for myself.
The problem with "Spieler", to some degree, is that it exists in two variants, and one of these is the default. Unlike "Person", "Spieler" actually implies a slight statement about gender. By using the default, you include more people, but some of them feel like they are only half-included. On the other hand, by using the female version, you make a statement, but you also actually include only half of the people. Both aren't ideal.