I'm not trans, so it's not really my place to draw the line here. But I'm tired of these "jokes" too. Even if they're genuinely meant in good humor with no ill intent (which often they aren't), they normalize bigotry, reinforce stereotypes, punch down at a marginalized community, and treat people like punchlines. They're also just not funny. The slurs make it worse. It should be called out. We should want a kinder world.
How to confront it depends on the setting. It sounds like you're mostly seeing this in videos and comment sections?
First, protect your mental health. Trolls and bad-faith actors never tire, but you will. Prolonged fights only let them paint you as emotional or unable to take a joke. They'll drag you into the mud and turn a decent instinct into "comment section drama."
Second, changing their minds shouldn't be the goal. They almost never admit fault. I aim to "smother the flames" instead. Keep responses short and flat. Don't sound offended, don't invite explanation. "That's a slur tbh" works. I often go with "bullying is kinda lame bro." If they pull the "it's just a joke" card, I might go one layer deeper with "didn't sound like one" or "you might want better material." After that, I stop responding.
The goal isn't to win. It's to suck the fun out of the thread. The people who would've piled on now have to sit with the fact that they're being publicly bigoted, and the attempt to make the rhetoric feel normal gets undermined.
Whatever approach you take, I respect it. If we stay silent, we let them dictate what's allowed in the public forum.