Oh yes, I definitely use the UP and DOWNvote.

If I see a mail that is not adding any value to me, or obviously plagiarized, I don't hesitate to use the downvote button. On Hive, I can't remember that I ever downvoted, but in Listnerds it's not rare anymore.

The tricky thing with this, however, is that it is different to everyone what they consider "adding value" and "quality". So there is something that needs to be addressed, I think.

What can be considered bringing value?

For person A it can mean that they are looking from their own perspective, and a referral link without any information can mean that they add value in their opinion. While person B finds it annoying and not adding value at all.

Same with the blogs that are shared. The goal is obviously to draw attention to your blog. But if the blog is not to your liking, is that adding value? Even if the sender obviously took a lot of time to work on the blog and mail?

Besides this, the amount of CTP you have staked also makes a big difference. And the amount of Hive / money you can, and are willing to spend to buy CTP. There are many variables here.