This is where we are in Shadowlands:
- Current tank specs: 6
- Current healer specs: 6
- Current melee specs: 13
- Current ranged specs: 11
Dragonflight adds 1 healer class and 1 ranged class.
Dragonflight with Evoker:
- Current tank specs: 6
- Current healer specs: 7
- Current melee specs: 13
- Current ranged specs: 12
This is nearly balanced, but not quite. Survival can help re-balance it. If you consider the community response to Survival since it's melee change - most of current Survival players are only playing it because of it's damage output, not because the spec itself is good. Then things could look like this.
Dragonflight if Survival turns into a tank spec:
- Current tank specs: 7
- Current healer specs: 7
- Current melee specs: 12
- Current ranged specs: 12
This incidentally makes Tank and Healer specs be 18.4% of the available specs, close enough to the 20% they should be to have a healthy population to enable Dungeons.
So this is the statistical case to make Survival into a tank spec. Blizzard I believe in your come back, you can do it!