Personally, I would never do business with a company that is racist, sexist or discriminatory in any way, but I defend the right to be racist, sexist, discriminatory or a general asshole in your private endeavours. I value freedom over feelings.
What if the same company controlled Twitter, Facebook, and Google? And what if that company decided to subtly give more prominence to political views they liked and less to ones they disliked? They could probably decide an election by doing that.
> If they wish to ban hate speech and apply strict disciplinary action to users who post such speech, more power to them.
And if they choose to give less prominence to politicians who think big internet corporations should pay more tax, do you still think "more power to them"? Are you sure you want them to have that much power?
Powrer corrupts. The more power an entity has, the more they will be corrupted by it, and abuse their power. That's why it is unwise to concentrate power in a few hands.
As it is, though, there are many social media networks, and users are free to choose the one that fits their needs. If a user finds Twitter too aggressive in weeding out misogynistic and racist hate speech, they can easily switch to Reddit, which takes a more hands-off approach.
I'd add their platform is every bit their own as that of a Mississippi lunch counter owners'. The ship you claim is protecting them sailed decades ago.
Further, it isn't their's after they IPOed, it's their shareholders, who might want a word with them about driving away half their user base....