a) is the best part of dtube, ending the era of youtube/google/corporate censorship

b) unless you're consuming random content, an echoChamber is always going to exist. It will exist offline too with any tribe or cult: any sports fan is only going to hear the good news about their team and not the bad, no matter what platform they consume that news from.

The real question would be: is the echo chamber generated by the content creator or the consumer?