Meta tags have been deprecated, the tags you are referring have not been confirmed to be added. Everything not explicitly announced should be considered not going to be added as I won't longer follow any long-term roadmap because I just don't like to work like that. From now on, I will only announce new features when these are under actual development, not earlier. Every day I have to deal with non-development random tasks, I can't be sure on when I will be able to add something in the long-term.
Is X feature going to be added?
There's no answer to that. Development here doesn't follow a long-term schedule, so the roadmap is always changing. Generally, the very next release roadmap is published just weeks before the final release, and that's the only announcement made for upcoming features.