What if we had a new kind of shield in PvP?

wirius

So I've been thinking about a "problem" in PvP that's existed for a while now. Progression rewards are competitive, unlike in PvE. What if there was a shield that cost an appropriate amount of HP that eliminated your player from the rankings, like a sandboxed character, but prohibited you from losing progression points if attacked? And to clarify for others like the respondent below, yes, that would eliminate all ranking rewards as well.

What are some upsides and downsides you guys can see to this?