So, in one breath you're saying that what was tweeted was inexcusable and in the other you're minimizing it because they're just tweets. Versus what? Does that format of communication make comments less relevant or hurtful than something said on stage or in an interview? Probably not in an era when the president mostly communicates over tweets. And quite honestly, I bet the reach for social media is far beyond whatever other medium would have made this more offensive in your mind. There's zero difference in how or where you write this stuff. If he had written the comments on a bar napkin that was made public, the reaction would be the same.
This is a huge gray area that the country is struggling with right now. If you say or do something racist/sexist/not-PC right now, you're immediately kicked to the curb. Its not even up for debate. See Rosanne Barr. I hate that show, but think of all the cast and the hundreds of people who work on the set, production, etc. who are now out of a job because of a racist remark one person made. I don't know what the right answer is, but the results seem a bit overboard to me when you consider everyone involved. How about instead of firing people, you educate them and force them to do some kind of public service work to counter whatever hurtful messages they previously spewed? Seems like that would be a lot more beneficial to everyone.
Now, If you said or did something racist/sexist/not-PC decades ago, should the reaction be the same? What is the statue of limitations on this stuff? Never? Look how many people have had careers ruined by the Me Too Movement based on things they did or said 20 years ago. I'm not arguing that we should ignore past comments or actions. But if you said something stupid when you were 25 and haven't said it since, is that really a good reason to all but exile someone? Seems pretty extreme. It feels like we could be doing something more productive than just banishing people.
I think it all just comes down to marketing and liability these days. Every corporation or organization is making these decisions based on the potential for negative branding and potential lawsuits. If Gunn is allowed to stay and the media jumps on this, then the public image of the who movie could be tarnished. At best, that means lower ticket sales. At worst, you could see morons working to link Marvel or Disney to pedophilia. Then there's the risk of more stories coming forward, lawsuits, etc. For better or worse, most companies have determined that it's better to cut bait and run.
At my last job, we had ethics training every 6 months where it was made very clear that you can be fired for just the appearance of a potential ethics violation. Whether or not you were actually doing anything wrong was irrelevant - that's how sensitive these issues have become. And if you want to argue that this is an alt-right issue, probably best to bring that to the Sarlacc Pit. I personally don't think its conservatives who've created this era of extreme political correctness.