And apparently there's some work being done on equipping Stryker's with the XM813, a 30mm Bushmaster autocannon that can fire programmable air bursting rounds. Which might accomplish the same thing.
There's definitely a need for armored vehicles better suited to urban combat. Maybe the Army's Armored Multi-Purpose Vehicle program will provide something. I don't know much about how vehicle armor works, but maybe there's room for optimization? I mean, it's not like the enemy here is firing APFSDS rounds, or using advanced ATGMs. It's all IEDs and RPGs at close range. I know there's stuff like having a V-shaped hull improves performance against mines, and slat and cage armor to deal with explosively formed penetrator type weapons, but I wonder if there's other techniques that can produce a survivable vehicle without needing a full, 60+ ton tank
There's also South Korea's K11, which is the same concept as the XM29, and seems to actually be used, though I can't find much info about its effectiveness.
The conclusions from the failure of the XM29 I believe was that it isn't trivial to operate a smart grenade launcher, and the 20mm grenade doesn't have as much lethality as you would like. But perhaps the K11 was able to rectify these issues. I personally think this need for precise, powerful fires could be filled by a crew-serviced weapon mounted on an APC/IFV. Doesn't even have to be a smart grenade, could be a special autocannon or something.