Isn't this all rather a moot point? Over the years I've followed many of the threads of people asking for tags or multiple contexts. I would suggest at least 50% of your users would like this. So why not give it to them? You can make an option one can turn off if one doesn't like it. What I object to here is the omni believes that it knows better than I do on how I should manage my tasks. This really comes across as arrogance. There are many different productivity philosophies, from GTD, ZenGTD, Covey etc. Each fits into the uniqueness of different people. I fail to understand Omni's approach of telling folks that Omni knows best? Apart from a basic GTD philosophy these other methodolgies don't work with omni. Good luck at trying to implement Covey's matrix. Yes, I've seen people post suggestions, but these work-arounds are cumbersome and demonstrate omni's infelxibility.
Over the years my productivity methodology has changed considerably and sadly, omni has not kept up with the times and still attempts to shoehorn people into its GTD method. This may be useful for folks whose methodology is identical to omni's but allows no leeway for folks who do things differently.
No doubt folks will say, you're free to use something else, but considering the quite considerable expense I've invested it's a shame that omni is so rigid that it won't even listen to half its users who want this option. I had thought that good developers listen to their customers, but that certainly doesn't seem to be happening here.
I was Covey trained before I discovered GTD and both approaches have pro's and con's for my work style. Tags make sense to me, a single context does not.