This is caused by the switch to HTTPS.

[Stack Overflow changed to HTTPS on May 22](https://meta.stackexchange.com/q/292058/164356), and guess what happened. Here are the awarded Announcer badges on Stack Overflow:

[![announcer badge graph 12017][1]][1]

This has a technical reason. Visitors coming from within the Stack Exchange network didn't count towards the badge as [they were filtered out using the HTTP Referer header](https://meta.stackoverflow.com/q/297923/559745). The problem is, HTTPS disallows cross-domain Referers<sup>1</sup>, thus visitors from within the network, even from child metas, can no longer be distinguished from outside visitors.

<sub>1: not entirely true, see comments for details.</sub>

  [1]: https://i.sstatic.net/L2Vq2.png