1. Yes. The bug you linked to is prominently marked "RESOLVED WONTFIX."
2. We are not sending DNS data to third parties "for analytics." We are openly and transparently conducting a DNS-over-HTTPS (DoH) experiment with a very small portion of users running Nightly test builds of Firefox. The experiment places a massive notification banner in the browser window with prominent buttons to disable or accept the experiment.
The details on DoH and how it improves both security and privacy are explained by Lin Clark in https://hacks.mozilla.org/2018/05/a-cartoon-intro-to-dns-ove... (HN discussion at https://news.ycombinator.com/item?id=17196415).
3. Firefox is Free Software, under an OSI-approved license. You're not "required" to build pocket, nor can or would we "forbid" you from removing it when you build Firefox.
...but you could also save yourself a lot of time and just toggle the "disablePocket" group policy: https://github.com/mozilla/policy-templates/blob/master/READ...
Still seems like a really bizarre thing to get hung up on when the extent of "Pocket in Firefox" is a toolbar icon and a section of the new tab page, both of which can be hidden with 1-2 clicks, after which they're completely inert. But hey, whatever floats your goat.
4. Yes, we gather a limited amount of telemetry by default. Unlike other modern platforms, this is always available for your own inspection (see about:telemetry and https://telemetry.mozilla.org/), and you can opt-out with a single checkbox. We actually reduced the telemetry we gather last year: https://medium.com/georg-fritzsche/data-preference-changes-i...