Is 3speak upvoting youtube videos?
It's really not that difficult to understand our stance, these chains have shown time and time again how malicious they are against Hive even after we've accepted it for a long time. Blurt has an abuser as their top witness and constantly showers people who have openly milked and abused Hive with rewards, they constantly use our downvotes as a way to market their platform even though a majority of them are used properly and carefully to adjust rewards or mitigate abuse. I'm sure I don't need to tell you about their governance or their leader who runs a project here that mainly leases out HP to abusers trying to win ROI back which all of it costs the other regular users more rewards in the long run. As for Steem I'm sure you're also aware of how they not only stole stake from me but millions of others in retaliation for not receiving a hive airdrop because they supported the centralization of the chain.
While we're not doing a blacklist as directly as the one you linked to, we're going to double check how people post content on the other platforms similar to all our other requirements some of which prevent us from voting for posts of your for instance as they already do quite well and our focus is on retention of underrewarded authors and preferably newcomers. Though we do vote for others now and then as well it's based on the fact that we think they bring a lot more value to hive than regular content creators and content does, the opposite of this is those who weaken Hive by posting the exact same content on other chains. Bear in mind that this only for those two affected platforms which is quite a minority of the internet as a whole, the rest of web2 has users which Hive can benefit from the author cross-posting content to and maybe eventually inviting them over to here as they feel loyal to the platform that's rewarding and supporting them as content creators and people.
Either way, had you been delegating or trailing ocd with your votes I'd understand if this decision would make you not want to support our votes any more, but going so far as to unvote our witness which also stands for a lot of other things such as the security of the chain it's quite a low blow and just feels like you're attempting to do anything to show dissent towards the decision that a majority of others felt was fair and agreed upon which is the reason it went into effect. I'm sure a majority on chain would feel the same way as there's only a minority who bother to post onto those copycat platforms these days after seeing how close to useless it is and how badly stake is and keeps on being distributed.