I think people are depending too much on creeping barrage. It's not a defensive model like the Stormwall. The stormwall can't shoot its covering fire templates at things. The creeping barrage effect is not very powerful, but it's also a free extra from attacking. You aren't trading any hits for it, and you can still boost it where needed. That aside, the Conquest still has its main gun, which is a big deal since it's a Superstructure weapon. That means it can aim and still easily fire on both arcs, so even against heavy infantry it has tools, just the tools are direct attacks, not indirect table control like the Stormwall.
All things considered, infantry can just walk around the stormwall's templates anyways, they don't have to go through them. At least with the Conquest it's the khador player controlling where the damage rolls are going.