That was a common complaint but the newest version doesn't do that anymore. Instead of immediately loading the new content, you instead get a little hover button at the top of the feed that says New Posts - that you now click to load the new content.

Because the old system was indeed super annoying, seeing something cool and then having it disappear in a long feed was annoying beyond belief.

It's a small change with the hover button, but one that is definitely a huge improvement. Sometimes the biggest UX changes are super minor - but their impact on a user's experience is massive.