Block their pubkeys from your feed? (Bit like wack-a-mole though....)

Create an anti-bot bot that automates the wacking for you?

Or like nostr:nprofile1qyt8wumn8ghj7ct4w35zumn0wd68yvfwvdhk6tcpyfmhxue69uhk6atvw35hqmr90pjhytngw4eh5mmwv4nhjtnhdaexcep0qqs8v3q3nvvwc444kfmeurgrtem392wkd8dlhedjch693j6kftake9g7pzcnf said... Embrace it!