First, let me preface this by me saying that I firmly believe that trans women are women and that everyone should absolutely be accorded the choice in who and how they live their lives, and shouldn't be subject to some rich old white person's bullshit over how they chose to live and who they want to be.
However, the drama surrounding this game has gone from 'yeah, there's a lot problematic with JK Rowling's opinions' to 'if you don't say you're boycotting this, you're deserving of death threats', which is a bit of a 2020's internet over-reaction.
Yes, she's a lousy person with lousy opinions, but then so are most of the people you read, listen to, watch, or otherwise engage with on a parasocial level. Humans are, as an almost rule, pretty terrible and there's lots and lots of bad, and avoiding everything ever made or done by someone who believes stupid shit, or says dumb things would be a pretty barren existence.
A lot of this, honestly, feels like grief over realizing that something they loved as kids isn't something they can hold on to and safely continue to love, because it's in the stewardship of someone who has clearly shown with both word and deed who she is, and that the utter vileness of JK's stances leech into everything she's ever done and they feel like it can't be supported. I understand this, and if this is you, then yes, by all means: boycott her, this game, and anything else she ever does.
But, at the same time, the behavior online makes this excessively reductive: the argument being made is that only one side can have a valid point or be right, and if you're not on our side you're wrong and the enemy and whatever happens to you is fully deserved. This is a bad place to live because it's a quick trip down misery lane if you look at everyone who may have a different set of priorities, and beliefs, or who is willing to separate the artist and the art as literally Hitler.
That type of reflexive aggression and distrust is exhausting, and doesn't serve any meaningful purpose other than to make yourself exhausted and crazy: trust me; I've been there many times and you end up angry and hateful and, frankly, stressed and scared for very little gain.
And of course, there are other issues being discussed surrounding the game which include the portrayal of goblins, which from a particular point of view, is indeed something that is problematic.
Several decades ago, someone making the movies decided the goblins should, kinda, look like stereotypical representations of certain ethnicities. Yes, that's bad, but goblins were crafted many centuries before that as gold-loving vicious little monsters. Goblins certainly predate the relatively modern stereotype that's being referenced in this case, and any immediate linking of any use of several century-old mythical creatures to modern society is entirely something you're doing in your own head.
I didn't miss that some of the people who worked on the game itself may have extremely awful opinions and have said terrible things, but, again, that's where we started: you can either make a personal decision that you want to play this game, or you think you can't stomach doing so, and shouldn't.
I do, however, fully agree that if you dislike someone or something they've said that you absolutely have the right to boycott or otherwise keep your wallet closed. Nobody thinks you MUST buy anything, but by the same token, you can advise and tell people why they might not wish to engage in purchasing something but there are limits on how righteous you can feel if they choose to decline because they're interested in whatever media you're angry about.
The stakes here are pretty low here: the absolute worst thing that happens is you buy a $60 game, and a rich person who already has more money than they could ever spend gets another $5. This isn't, honestly, actually going to make any meaningful difference in her opinions, actions, donations, or shit-tweeting.
And at significant risk of falling into whataboutism, it's very hard to be extremely into boycotting a video game that doesn't really have any major global impact when almost anything else you consume on a daily basis is worse. Remember, kids, there's no ethical consumption under capitalism, but picking your fights so that you only go after easy targets that don't matter because it won't really inconvenience you is not taking a moral stand.
If you want to boycott something that is from someone that offends you, great: but that is a personal choice that you're making for yourself. This incessant argument that every one MUST agree with you on the internet or they're worthy of death is relatively new, and utterly destructive for an open and free society and shouldn't be something that's tolerated and shouldn't become the default over every outrage.