Can you make any tank work up to a +25? Sure, but what you have to ask yourself is whether the extra effort that comes with that choice is worth it.
A great example was BFA when Prot Warrior dominated the M+ scene. You could most certainly make a Guardian druid work, but you had to use a very specific composition to do it and if you didn’t have that comp, it wouldn’t; at all.
So is it easier then for you to change the spec you play rather than also potentially force one or more of your friends to also switch specs to make up for your shortcomings all because you want to play the trash-can tank spec?
At the time of this post with regard to M+ (on a +15 key with Fortified):
- Guardian is 55% behind the next tank in raw damage.
- Guardian is now the lowest HPS tank, behind Protection Warriors.
Why would you play a spec that is so far behind the current mark?