It seemed that he was trying to move the existing users from costing him money to at least a break even situation. In this case grandfathering existing users would have propagated a negative cash flow.
I have been too. I was surprised to find that HN didn't show up on Google a couple weeks ago. Yes, it looks like I was wrong. No, pg isn't changing titles because of SEO.
For the Chrome extension, you probably don't need to request permissions on tosdr.org. If you send CORS headers from that site, you will be able to make requests to it without the permissions.