ignoring and deleting/blocking/etc is the best response to all kinds of bad stuff online, but especially when someone has very little power or reach. there are situations where you can argue "responding to this awful person is useful" if they're famous and well-known-- correcting widespread misinformation, embarrassing them publicly, whatever-- but that's only true if everybody already knows about them. if you respond to someone with 20 followers to dunk on them, even if they are a huge jackass and/or directly insulting you, you are:
Helping more people see their message (especially on sites with an algorithm like X/TikTok/YouTube etc, where interaction boosts a post's popularity)
Spending your time writing a response to someone who only wants to harm you
Encouraging copycats who also dislike you and see your response to do the same to waste more of your time and get their own free exposure
Making the sentiment behind their message look more popular and common by showing it to everyone
(and a final more meta problem) Contributing to a social media environment where it's normal to do all these things and feed the trolls.
All of this is true regardless of how you respond, even if you make them look like a total idiot. The best move is not to play. This goes for messages directly targeting you and more general bait/asshole/etc posts in general (eg, anon hate but also people who post on Twitter about how they love eugenics.)
Think about this in terms of likely outcomes (like I am always saying). The outcomes from ignoring assholes are almost always better than the outcomes from responding. Unless someone is already in a position of power you are giving them more power when you respond. (And even if they are in a position of power it's often not useful, but this is about the more common case where they're some random idiot.) These people want a response. They may be savvy and know all this I've said, or they might just be impulsive morons, but either way they benefit when you respond. Deny them that. Attention is valuable social currency.
There are cases where "Should I write a response debunking this post that's pissing me off or should I ignore it?" is a real coin-toss, and I get that. But there are also a huge number of situations where it's not a coin toss and it's straightforwardly helping the troll to respond to them. In those cases, don't dignify it with a response. Screenshot it and chat with your friends about it in a group chat if you feel the need to talk about it.
refusing to engage is an underused strategy because it isn't "fun" and people generally don't see you doing it. it doesn't feel like you're accomplishing anything because it's a negative: you don't get to see the counterfactual where you give them attention, so it doesn't feel like success to deny it to them. but sometimes doing nothing is the best option, its benefits just aren't as visible! it's a very useful strategy and you shouldn't forget about it.
