People on the right don't have the power to really cancel anything anymore. Some on the right may attempt to cancel stuff, but it is mostly not effective.
>Colin Kaepernick and kneelgate
Kaepernick wasn't canceled by the right. He just wasn't the best player out there and didn't get onto another team. He now is making millions from Nike and other deals all without playing the game. If this is what be canceled is like I would gladly sign up.
>calls to boycott Starbucks for celebrating an inclusive holiday season, rather than Christmas in particular
There was an attempt but nothing happened. As far as I know Starbucks' revenue didn't even drop (but I haven't really looked into it). Again a complete failure of a cancellation.
>republican voters "cancelling" Mitt Romney and other republicans for being vocally anti-Trump, even though their political principles have not changed
Romney still has his senate seat and is still on all of the committees he was original on. There is no cancelling here, unless you mean voting out a politician is canceling.
>The long, ongoing fight to teach children about LGBTQ issues in public schools.
This is a bit more complicated. Some people believe it is more than just an objective teaching that LGBTQ people exist and you should treat them as any other person but more of encouraging people to engaging in such behavior. Some people also accuse the schools of focusing on random LGBTQ people or assuming people's sexuality when they weren't married in history class instead of focusing on more important people or just the facts. I don't think I was in school when this was going on so I can't really comment on what it is like.
> Teachers can be fired for simply revealing to their students that they have a same-sex partner.
I have only seen this in private religious schools. In theses cases the teacher agreed to publicly follow the church's teachings and they failed to follow their employment contract. You shouldn't work for a church if you disagree with the church's teachings.
>Ellen comes to mind as an example.
Are you saying Ellen was canceled for being LGBTQ? I am pretty sure she is being attack for being abusive to people who work / worked for her.