This is also why the most hilarious anti-feature of Jira, supposedly a tool to manage agile teams, is how every ticket has one person assigned to it. If you do sufficient pairing, the person assigned to a ticket is completely useless. Also why performance measurement from the outside of a team is always going to be dubious.
Every team knows their best performers, and their lowest performers. The number of points aren't going to line up with performance most of the time, precisely because time helping others is never going to show up. And if suddenly getting help lowers your review, you are going to ask for less help, not more: Trading accuracy in external performance tracking for lowered team performance sounds really dubious.