[Existing4190]

You are right. My comment can't solve the whole story.

Still, some middlebox/stateful firewall/etc. messing with 169.0.0.0/8 is plausible.

[xnyan]

Actually I think you might still be right. Ping uses ICMP, which is almost never blocked in my experience. I learned that because early in my career I too assumed a successful ping = TCP and UDP also work.

[js2]

Filtering + established connection tracking:

https://news.ycombinator.com/item?id=39822214