When I Focus on a few projects or folders, I typically can go into the Tags view and typically see actions within the Focus projects / folders and not the zillions of actions I have for a particular Tag.
Just this morning, the Tag view stopped “adhering” to the Focus I was in. Well, it would, then when I create a new tab with a different Focus, all my actions for a particular tag would show up in the original (much more) Focus tab.
As @deaghan mentions, this should be fixed in OmniFocus 3.6.1, which we released the final version of within the last hour. Please let us know if you continue to have problems!