Same dynamic exists in Pkarr because relays. The difference is that Pkarr queries the DHT and relays in parallel by default and will always do so, because why not. So a relay used by everyone is very unlikely to be a single point of failure... because the parallel query to the DHT is not expensive.

Even if you are in browser, if only one of the relays you are using in parallel is honest and publishes to and read from the DHT, then no matter how small and obscure it is, it is still bypassing the malicious relays.

It is just too hard to censor.