When you get a notification that there’s a new post, click on the number - that should auto-drive the thread down to the newest post. At least it does on my work computer, my Chromebook laptop, and my phone.
For instance:
When I clicked on the Silliness & food funnies 2025 highlighted at the bottom of my Unreads, it went to paryzer forking my post on that thread (which was 1022nd post out of 1025 total posts in the thread).
ETA - Never mind. I see it’s the iPhone that’s the issue. Sounds like the bacon strips is the way to go. Not that baconing all the time is a bad thing. Well, except maybe not as heart-healthy as it could be.