security – Can dishonest miners spam fake blocks?

How, if at all, does bitcoin disincentivize spam blocks by adversarial/dishonest miners?

As I understand it, blocks are propagated throughout the network using a gossip protocol. If that’s true, I think it means that each miner is aware of some subset of other miners to which they can propose blocks to be included in the blockchain. Is that correct?

If so, could someone theoretically write some software that simply proposes bad/fake/spam blocks to other miners as a DDoS attack? If not, why not? If so, do these attacks happen with any meaningful frequency?