I assume it will become dangerous to spam tags if hf21 arrives and there are free downvotes.

Hopefully, although I hope the community accounts get a reasonable amount of work done here too.

Better to focus on decent content in one community and earn 100s of tokens that get dust from 7 or 8 communities and waste people's time.

Agreed, although many don't seem to understand this.

... one thing I propose for SPS if it happens is make a tag filter so we can hide these spammers from our searches for relevant content.

I suspect we'll be told to mute these people. Bugger, I could be doing this across 10 accounts or more :)