The only thing that really pressed my team to give up on the infected ground elite was time. The second deciding factor was that Critical regenerators are not for sale from any regular merchant, and on the exchange they go for 250,000 EC minumum. Walking into the boss room typically results in getting caught in a cone crossfire, and with injuries it's a one shot wipe for most of the team. An engineer or medic might survive the first hit.
We haven't done the Cure or KA elites yet, but so far I've seen one person get some rare borg salvage by running the Infected Space STF on normal, and apparently they only dropped because they completed the optional objective. From what I can tell, the M.A.C.O. set will be very useful for surviving elite, with the shield buff two pieces give. So I'm fairly certain Cryptic is looking at it as a progression scenario. Your mark XI gear will not actually be as good as the Mark X M.A.C.O.
From what I can tell, the elite ground isn't as large in its disparity as the space missions, from what the STFs used to be. Drones do hit harder and live longer, but over all it didn't feel like we had no chance to win, until Critical injuries added up to the point where we just couldn't survive the opening salvo against the tactical drones in the boss fight.
If we could get a shop to buy critical components for ships, and critical regenerators for ground, it wouldn't be nearly as debilitating, but would still require investing in resources and carrying them into the fight.