It does seem that way at first, but (stipulating that it's a thing) cancel culture is based on someone's actions. Discrimination is based on someone's attributes that they cannot change, that are fundamental to who they are. This is why deplatforming someone who's being a racist (or a cop, or a Democrat) is not the same as deplatforming someone because they're LGBTQ.

You can go a little further with this into ascribed vs. achieved status [1][2]. I'm not saying achieved status discrimination is good or OK, nor am I saying it isn't. But it's not the same as ascribed status discrimination.

[1]: https://en.wikipedia.org/wiki/Ascribed_status

[2]: https://en.wikipedia.org/wiki/Achieved_status