Lets just add shit pathing for infantry units^^
Like in SC one.
Starcraft 2 added better pathing, and its the reason they got deathballs.
Honestly, instead of such stupid Ideas, I would rather give troops a debuff when they are blobbed.
As I see it there are 3 ways to reduce blobbing:
1. Give them a direct debuff. We could call it whatever we want

Not enough supply in the area, enemy shots will hit somebody, enemys get a moraleboost when being outnumbered, logistics or the chaincommmand get disturbed, whatever. But that would be pretty radical, and somewhat lazy.
2. Better options to deal with blobs/ greater risks with blobbing. This could be mortars who get cheaper flaming barrages, or generall bigger (and maybe weaker) aoe. Or better MGs. The biggest problem here, is to find the fine balance, where the units are specifically better against big blobs, not against everything.
3. More incentives to spread out. Mostly through mapdesign, or broader mechanic changes. For example maybe you get bonus ressources when you have a unit in a territory (enemy or friendly), but more than one in the same area gives no advantage. It could be a supply thing, lets say the upkeep gets reduced for 1 unit per sector?
1, would be the easyest solution, but not very refined.
2 would be relative easy, but will require some balancing.
3 is the most complicated, and would need the most balancing afterwards.
So I would just go for 2. Just buff some AOE units. Its relative easy, then the Meta will adjust, and you can balance it a bit.