There's no universal tag blocking but you can block tags per user appearing on your Reading Pane. It's a paid feature (The minimum purchase of paid account is 1 month for $3, with a very small discount for buying longer amounts of time).
https://kore.dreamwidth.org/1321059.html takes you through it. I used it for the first time earlier today, although when I followed along I hadn't yet created a Default filter, so I did so, and threw all my current subscribe list into it, then added the specific tag from the specific user that I wanted to block.
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Date: 2018-12-07 09:09 pm (UTC)https://kore.dreamwidth.org/1321059.html takes you through it. I used it for the first time earlier today, although when I followed along I hadn't yet created a Default filter, so I did so, and threw all my current subscribe list into it, then added the specific tag from the specific user that I wanted to block.