It depends on how far the barbels have eroded. If they're completely down to "face level", they might not grow back. But if they're just shortened, they have a much better chance. Keep your nitrates low will help on any substrate.
I've wondered about that as well. I've kept corys in with pea gravel and finer natural gravel and never noticed barbel erosion, but I always kept nitrates very low (~10ppm or less) with 50% wc's at a minimum.
My nitrates are always low at about .5 with occasional .10. I think the problem is that I used that black eco-gravel as the base level of my substrate then put smoothed river gravel over that, but during gravel vacuuming it has brought up the rougher eco-substrate to mix in with the regular gravel. I think that's what is doing the barbel damage. Two of my corries have no barbels at all now. I'm setting up a 10 gallon with sand substrate and want to transfer those 2 corries to see if they can recover, but then I worry about the other 3. If I transfer all five into the sand substrate tank, what can I get for my 29 gallon? Will Kuli loaches do the bottom feeding like the corries?